All right there my friends so now we have our coding environment all set up hopefully you've got V s code installed on your computer and that package live server because we're going to be using this to preview our pages in the browser I've already gone ahead and right click and gone to open with live server so we can preview the website right here there's nothing there at the minute but that's because we have no content in the Page but if we had an h1 over here that says page title save that and view over here
now we can see that okay so what I'd like to do now is show you how to add JavaScript to a web page and where we have that JavaScript so first of all we're where do we add JavaScript to an HTML page well we can add it anywhere between the head tags or anywhere between the body tags so for example I could come beneath the title and add some JavaScript right here now the first Thing to do is create a script tag like so and we place our JavaScript between those tags so I could say
something like alerts and then hello world semicolon and I don't expect you to understand what this means at the minute this is just some random JavaScript to demo where to place it on your page okay but if I save this now then this script is gonna run and this thing right here this alert function this creates a popup on the screen so if I save it go to the Browser we see that pop-up hello world we press ok and the rest of the page loads now placing the script inside a head that's absolutely fine you
can do that but in some cases it's going to cause some loading issues so 99% of the time if you're adding javascript to a page I would do it not here but instead at the bottom of the body tag just before the closing body tag right there place that in and scoot it back if I save this it's gonna do exactly the same Thing we see the pop-up okay and then the page loads okay so this is fine when you have a small amount of JavaScript but if you have a large amount of JavaScript with
different functions and it goes on and on and on in this page then it would be better to somehow externalize that JavaScript and put it in a separate file then just link to that file from the HTML page this is a bit like when you do CSS right if you wanted to you could add A load of CSS in the head in some style tags but most of the time when we have a lot of CSS instead we do a link tag and link to an external CSS file so that's what I'm going to do
most of the time inside this course probably 99.9% of the time in fact so I'm going to comment this out and instead I'm going to link to an external file so I'll create that file first of all right click over here go to new file and we'll call this sandbox j/s so all JavaScript files have This dot j/s extension that's important so now we can link to this file from index let's come down here we still need our script tags right here this time we say sauce is equal to and then the path to this
file so it's just sandbox es ok so now we have that linked top if we write some JavaScript code inside this file it's going to run that when we load this page in the browser now over here we don't need to do any more script tags the script tags are right here okay so We can just write our JavaScript directly in this file now so I could do exactly the same thing alert then hello world and then close that off with a semicolon save and come over here and it does exactly the same thing okay
so this is how we're going to be working in this series in this course we're going to be linking to our scripts from the bottom of the body tag to an external file now there's one more thing I'd like to mention and that is that in JavaScript We use semicolons like this to mark the end of a statement so this right here this is a JavaScript statement and this semicolon is marking the end of it it's like a full stop at the end of a sentence is our way of ending a line of code that
does something imagine having a book and that book had no full stops or periods then you would not know when to take a breather right so that's the case in JavaScript as well this marks the end of a particular statement now Technically in a lot of cases if you forget your semicolon then the code will still work and it's not gonna give you an error they're not required a lot at the time so if I delete that and save then preview this in the browser everything still works right now there are some developers who don't
use them at all but in some cases if you don't use them then you will get an error and I think especially when you're first starting And you don't know the language that well or why you would be getting an error it's always a good habit to get into to add your semicolons at the end of a statement okay and we'll talk more about this as we go along in the course so anyway there we go that's how we add JavaScript to a web page so then for this course I'm using Google Chrome as my
browser of choice hopefully you are too it comes with some developer tools and a console which will really help us A lot when working with JavaScript now you can open up the tools panel by pressing f12 inside your browser and that opens on the console tab right here so the console is like a sandbox area in a browser which we can use to test JavaScript code we can print out values and basically just play around in it so I could type some JavaScript code directly inside here and just press ENTER to run it for example
we'll do alert again alert and just say hello and Then press ENTER and it's going to run that JavaScript for us so it's a nice little area to play around with some code when we're learning now we can also log things to the console this thing right here from our JavaScript file so say for example I wanted to output some kind of value over here in the console when this javascript file is run I can do that I can do that by just saying console dot log and then in parenthesis what I would like to
log to the console So for example I could just say one and then end this statement with a semicolon save it and come over here and we can see this one value over here now if we wanted to add something else we could just come below and say console dot log and then - and this is going to run in order because JavaScript runs from top to bottom so it's going to log this first then this so if we save that and preview we can see one then - now don't get too hung up about
what this all Means like dot right here and this log function and the console don't worry too much about it just yet we're going to cover all this kind of stuff later on just know that this is a function right here that we can use to log out values to the console and that is really going to help us when we're learning the language so for the first few chapters of this course while we learn the building blocks of the language we'll be using this console to test our code and See some results and then
later in the course when we've learned all of the basics we'll move on to manipulating content in the browser itself in a webpage and other cool things too now if you're not using Google Chrome then shame on you but most likely the browser that you have has some kind of console in Firefox you can open this by pressing ctrl + Shift + K and in Internet Explorer use f12 to open up the dev tools then hit the console tab at the Top to see the console okay so now we know how to use this console
over here and how we can log to the console from our JavaScript file in the next video I want to move on and talk about sort of the most basic concepts in the language variables and constants so then one of the most fundamental things in JavaScript is this notion of variables and what variables do is give us a way to store a value like a name or a number or an email and then use that value Whenever we want to later on in the file now there's a few different ways we can make a variable
the first way to create one is by using the let keyword so that would look something like this we say let's then the variable name for example age and we set that equal to something so I'm going to set it equal to 25 then we end this with a semicolon okay so you can think of this as saying let this variable called age equal to the value of 25 now this value is now stored in Memory and we can access it later on using this variable name so I could just come down here and I
could say console.log and then the age variable which is what we called it and that's going to log this to the console so if I save and check it out in a browser we see 25 okay all right then let's do another example I'll say let Year equal to cero one night and we're going to save that and we want to log this to the Console as well now I could duplicate this on to the next line but in one console log statement we can actually output several values and we do that by separating them
with a comma so I could just say age comma then year and that's going to output both of these values sort of a save now preview we can see 25 then 2019 okay so this let keyword right here creates us a variable and if we want to override the value of those variables later on we can do so I could Come down here and I could say H is now equal to 30 and what that's going to do is look at where we initially defined age grab that value and update it so the age is
now equal to 30 we don't have to say let anymore we just take the variable that's already been defined and change the value so now if I say console dot log and then age underneath hopefully we should see 25 to begin with then we reset the value of the variable then this should be 30 so save it and Preview and we see 25 201 9 and then 30 cool okay then so what if we wanted to create a variable but we don't want the value of that variable to be able to change well in this
case we'd use a different keyword than let we'd use the Const keyword so let's now do another variable but this time use Const and this creates as a constants we still give this a name so I'll call this points for example and set it equal to something I'll say 100 and this creates A variable much in the same way as the let keyword does and we can log it to the console so I'll say console dot log and then points and we're still going to see that over here we can see 100 but now if
I try to override this value the same way we did with this then it's not going to let me you've icy points who's now equal to something else like 50 save it then we get an error over here we see assignment to constant variable we're not allowed to do that we use a Constants if we don't want this value to be overridden by mistake any point okay so something that's going to stay the same throughout the whole program now both of these key words Const unless they are fairly new additions to the JavaScript language there's
a modern way to create variables and they're what I would recommend using almost 100% of the time now I will generally use let if I think I might change the value of the variable at some point or sometimes when I know that I don't want to change or overwrite the value of a variable I'll use Const instead but there is another older keyword that we can use to create variables too and that's is the VAR keyword okay so before let and Const came about this is what we'd use now I'm just going to do a
quick demo and show you this so I'm gonna say var then name this variable score and set it equal to 75 then I'm gonna say console dot log school so this should still work and Exactly the same way I'm gonna get rid of this thing where I try to override the value of points so we don't get the error save it and down here we can still see that school okay 75 so this right here this VAR keyword this is the older way to create variables before let and Const came about now you still will
see some developers use this but in this course because we're doing a modern JavaScript course I'm just going to be using Const And let okay I just wanted to let you know about that that older way of creating them so then when we give our variables either let or comments down here different names these are the names of the variables there are a few different constraints first of all there can't be any spaces we can't say something like my space age okay it has to be one complete word typically if we want to use two
or more words in a variable we use something called Camelcase which is something like this my and then we start the next word with a capital letter my age and it's called camelcase because it looks like the hump in a camel's back alright so that's the first constraint we can't use spaces now the second one of variables can taine only letters numbers underscores or dollar signs but they can't start with a number they can start with any of those other things that just said underscore or Dollar for example but they can't start with a number
so I can't say 5h notice we get that squiggle line okay and finally there's also some reserved key words in JavaScript that we can't use for variables because they're used for other things for example let and Const so I couldn't create a variable that's called Const right that won't work because this is a reserved keyword in JavaScript for creating constants so what I'm going to do is leave a document Attached to this lecture which is going to outline all of those different reserved keywords so you can check those out for yourself so that's just a
few constraints when we're naming these variables also when you do name things try to make the name meaningful so that if another developer looks at your work they would say yeah I understand what this is meant to represent okay so one last thing in this video I'd like to show you and that is comments so say for Example I want to make some kind of comment in this code for another developer when they come to read this file I could do that I could say something like this log things to console and that right here
is grayed out this is a comment and it's a one-line comment and I did that by adding two forward slashes at the start so when JavaScript runs this file it's not going to run any comments I can also use these to comment out certain things Like this if I just want to test something with a console log but then don't use it later on I can comment it out and now this is not going to run so that's how to do a single line comment using double forward slash I can also do a multi-line comment
by saying forward slash and then asterisks and then we need to close this off at the end of the comment like so and we can place it somewhere else we could place it up here and then all of this is commented out as Well okay so that's just a couple of ways to comment things out also there is a keyboard shortcut I could highlight something I want to comment out and press ctrl and /and it's going to comment those out I can do the same thing to uncomment those as well all right now there is
just one final thing a promise in this video I want to tell you about and that is when we're using modern JavaScript techniques like let's and Const and Other things in the future they might not work in 100% of browsers out there old browsers like Internet Explorer 11 and things like that they don't support a lot of the modern features so I would strongly suggest that you use something like Google Chrome as your browser for this course in one of the last chapters we are going to look at supporting all browsers using things like bubble
but for now I would recommend using something like Google Chrome for the Rest of this course okay then so we've seen how to store different data or values in variables we saw that in the last video but at the minute all of those different values were just numbers we did things like an age a year or points or a school they were all numbers right and that is just one data type in JavaScript now in JavaScript we work with many different data types the 7 in total they're all listed here and they all have their
own unique properties and The things that they can do so we're going to have a quick run-through of all of them now but as we go into the course we'll be looking at each one in much more detail and using them all as we go through them so then first of all numbers we've seen them in action already things like 1 2 3 100 or 3.14 even decimals like this they are all of the number type the next one right here this is a string and strings are basically a series of characters in Single or
double quotes like a sentence or some kind of email like this okay the next one billions over here they are a special logical true or false value not in quotes they're not strings and we use these for evaluating conditions now this next one null over here this is a way that we can explicitly say that a variable has no value so we could create a variable but set it equal to null to say that that variable doesn't have a real value yet okay now it's Closely related to undefined here but the difference is one defined
is a type that's given to variables automatically by the browser that have not yet been defined so these are both empty values but this one right here no we explicitly set to a variable this one is automatically given to variables when they're not yet defined does that make sense okay so the next type this object thing right here these are more complex data structures which can have multiple Different properties and functions meaning they can perform various different things now a lot of javascript is based around using objects and there are many different object types or
types of objects built into the language which we can use out of the box there's a whole subset of built-in object types like arrays dates object literals in fact you might hear the same everything in JavaScript is an object which is a huge simplification but it stems from a Source of truth but don't worry about that now there will be a whole chapter on objects later on in the course and we will look at all the different types of objects we can use in JavaScript as well things like arrays and dates and object literals okay
and finally symbols they are a new addition to the JavaScript language which are closely linked to objects too so we're going to discuss them more later in the course rather than now so For the rest of this chapter we're going to be looking at these different types of data strings numbers null undefined and boolean z' we'll also have a quick look at arrays which fall under the object type down here it's a type of object with its own unique properties but we use them all the time in JavaScript and they're quite simple to learn which
is why I'm covering them in this chapter now a variable which we've already seen can Hold any data type be it a string a number null boolean and object etc we don't have to explicitly say what type of variable it will store on what type of data it must all and we can override a variable with a different type too meaning if we make a variable and store a string in it to begin with we can override it later on if we use the let keyword that is with a number okay so we can change
the type of variables and for that reason javascript Is known as a loosely typed language in contrast to a strongly typed language like Ruby or Python now I don't want you to feel overwhelmed with all the different types I think you have to remember them all don't focus on that because the more you code with JavaScript is gonna come naturally to you over time and we're going to be referring back to this type chart anyway throughout the course to reinforce your understanding of them the last thing I Want to do is scare you off so
as long as we have that idea of tights simmering in the background that is more than good enough for now so then the first data type I want to explore in more depth strings so we use strings to store letters numbers or other characters and we could use them to store something like a name or an email address or something like that so what I'll do is just log to the console a simple string so I'm going to say Console dot log and remember we store strings in either single quotes or double quotes now they
behave the same way doesn't matter which one you use but if you open with a single quote you close it with a single quote if you open with a double you close it with a double I generally use single quotes for Strings but sometimes you might see me use double quotes if I needs it so I'm just gonna say hello world and put my semicolon on And save this and we should see this logged to the console now we don't see the quotes right here but that doesn't matter over here we add quotes to make
a string okay so then we can also store strings inside variables so I could say let email equal to some kind of string for example Mario that's the net Ninja code at UK and now that is stored in this email variable so if I wanted to I could log this to the console by saying Console dot log and then email so if I save this we should see both of those things now logged it to the console cool okay then so imagine we have two strings and we wanted to join them together well that is
called concatenation so concatenation is just a fancy word for joining things together so if we have two variables for example let's first name equal to Brandon and then we'll say let last name equal to Sanderson what I want To do is join these two different strings together now I can say let full-name equal to first name plus last name so this is string concatenation we use a plus sign to concatenate one string to another string in other words to join one string to another string so if I say console dot lock full name now then
we should see this in the console now if we take a look over here we can see Brandon Sanderson book there's no space in between the two names so what We could do is concatenate after the first name a string which is just a space then we concatenate the last name so were concatenate in three different things here the first name then a string which is just a space then the last name so now if we save this we can see Brandon Sanderson with a space in between okay so we can do this kind of
thing so we can also extract a single character for our string that we have stored for example of this one by using Square bracket notation so I'll show you what that means I'm just gonna say console dot log first of all then we're going to take the full name and say for example I want the first letter in that name then I can use square brackets and I pass in 0 now we pass in 0 because javascript is a zero-based language meaning it counts from zero up rather than one up so in JavaScript this is
position zero the first letter the second one is position one then two then Three so forth okay so zero actually gets meet the first character so this is why we use square brackets after a string to get a single character in a particular position so this should get me B and we should see that in the console cool now if I wanted to change this to another I could say two and that should get me the a because 0 1 2 so if I save it preview we see okay so that's how we get a
single Character using this square bracket notation on a string now a string also has methods and properties now one such property is the string length so we could say something like this console.log and find the length of the string that is how many characters are inside the string by saying full name dot length and that gets us the length of this string right here so if I save we see 17 and if we were to count the characters which I'm not going to do we Would find that the 17 characters and this right here this
is one of them at space okay so that's the length property and final extremes has several different functions associated with them now these functions are called methods and there is a technical difference between functions and methods but you're going to hear them used interchangeably so basically a function is a snippet of code which performs some kind of specific task a Method is just a function that's associated with a particular object or datatype and we're going to discuss the technical differences later on but the two words essentially mean the same thing so if I say method
or function it both mean that we're performing some kind of function that does something and a string has several methods several functions that can do things okay so for example we have a method call to uppercase and what that does is take the String and it turns it so that all the letters are uppercase so I could say something like console.log we do the string we want to use the method on so full name then we say dots and we say to upper case so this is the method name so when we have properties we
say dot and then the property name but this isn't a function this is just a property of the string it's not actually performing some kind of snippet of code to do something it's just finding out a property of the String this down here see what the case this is a method a function which actually does something it takes our full-name and it turns it to uppercase so because this is a method what we do is add brackets or parentheses on the end of it so whenever you see something like this dots and then some kind
of name and then parentheses it means that this is a method of whatever we're using it on okay in this case it's a string method So if we save this now we're going to see that it's going to take our full-name our string and it's going to turn it to uppercase and then we're going to log that to the console so we can see now Brandon Sanderson in all uppercase okay now throughout other methods as well I'm going to show you another and this time what I want to do is store the results inside a
variable so I'll say let result equal to full name dot to lower case okay now what This does is the opposite it takes the full name and it's going to turn it to lowercase but instead of logging this to the console like we did up here what we're doing is actually taking the value that this gives back to us and we're storing it in a value called result a variable okay then what we could do is use this later on for now we are just going to log this to the console console dot log I
just wanted to show you that we can store the values that are Returned to us right here so I can say results like so save it and we can see this in the console now it's all lowercase before up here normally it's started with a capital both names but now it's all lowercase now I want to make one thing clear these methods right here they don't actually alter the variables themself the original variable this full name so if I was to log out the full name as well we're gonna see that it's still going to
be Brandon Sanderson like this capitalized so if I save it preview in a browser we can see that we get this one right here Brandon Sanderson with just a capital letter at the start of each name so these methods they do not actually alter the original value that we use them on now some methods do alter the original value and some methods don't so these are just cases where they don't alter the original value now sometimes we can use methods which expect us to give them a Certain value so for example I'm gonna use another
method down here but before I do that I'm going to say let index equal to the email I remember that email value was this thing up here we said email is equal to Mario at the net ninja code at UK so I'm creating a variable called index I'm setting it equal to e mail dot index off so this is a method and it's going to find the index of a certain character inside this string so by index I mean the position So what I want to do is tell it to find the index of the
at symbol okay so I can pass in as a string in quotes the @ symbol to this method now this thing right here this is called an argument but you might also hear them being called parameters including what I talked about them because there are easy words to get mixed up but technically speaking when we pass a value into a method like this this is an argument okay so what that's going to do is find The index of this inside that string email and it's going to return that value to us which were then storing
inside this variable so now if I say console that log and then the index like so I'm gonna save it come over here and we can see five now if we count though zero for the first position then one then two then three then four then five okay so it gets us that index so then the takeaway points here are that strings are a series of letters or Numbers and by the way we can add numbers in here you know that's a valid string any kind of character we want to in here that's absolutely fine
these just all go inside quotes so strings are a series of letters numbers and characters in quotes they have properties like the length and we use dot notation to get those properties they also have methods which are the same kind of thing as functions the built-in snippets of code that do things For us and we denote methods and call them by using these parentheses at the end of them so strings have methods as well as properties and we're going to explore some more string methods in the very next video all right then my friends so
we've already seen a few basic string methods in the last video and remember methods are just functions that belong to a specific object or object type now let's have a Look at some more methods so first of all I'm going to create a new variable called email and set that equal to Mario that's the net ninja code at UK and let's spell this correctly okay so now let's use some methods on this variable right here so the first one I'm going to show you is called last index off now I'm going to store the results
in a variable called result and set this equal to e mail dot or last index of so we're using this method on the email Which is the string and this method finds us the last index of a particular character in that strings so for example say I want to find the last instance of I don't know something like n then we pass that in there as a string right the string is the argument that's going to find us the position of the last n it comes across inside this string which is this so the position
of this end so now let's come down here and say console dot log or results just to see if this works And we'll preview this in a browser and we can see 14 let's just quickly count 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 spot-on okay so that works all right let me comment this out and let's move on to the next one so next I'd like to do a method called slice and what slice does is essentially slice a section from the string so let's do this we'll
say let results this time equal to the email which is the string dot slice and inside we pass in two arguments this time not Just one like we have been doing up here now two arguments now the first argument is where we want to slice from so if we want to slice from the beginning we say position 0 the next argument is where we want to slice 2 so if we want to slice to position 10 we say position 10 and if we save that we're still logging out the result which is this over here
so let's save it for you in a browser and we can see this okay so it slices that section from 0 to position And it logs that to the console now when we do it here so let's change this to 5 and we should just get the first five letters which is Marriott cool so remember the first argument is where we go from the second argument is where we go to ok so we could do this if we want you to from 2 to 5 and we get something like real alright so the next one
I would like to show you is similar to slice and we'll set results equal to this so let me solve equation and what We're going to be doing with this is making a substring from this it's a very much like slice but the two arguments represent something slightly different so the first one is still the start position so if I say 0 I'm saying start from position 0 but this time the second argument is how many characters we want to go along so if I say 10 then it's going to get us the first 10
right which is the same as 0 to 10 here but if I say 4 to 10 then it's going to go from Position 4 and it's going to carry on 14 so I'm gonna save this now and let's view this in a browser and now we can see it goes from position for up to position 14 it gets 10 characters ok so that's the difference between these two methods ok so let's move on to the next one I'll say let's result equal to email and this time we'll use a method called replace now what replace
does is replace a certain character in the string with another character so it Takes two arguments I'm going to say m and if I pass in the second argument to be W then what it's going to do is find the first M inside this string and replace it with a W now the first M is right here so let's save this and test it and we can see now we get worio at the net ninja so it's replaced that first M cool okay now so let's do another example of this method what I'm going to
do is say this time let results equal to email don't replace and we're Going to replace this time n with W so what you think is going to happen here because we have several ends we have this one this one and this one well if I save it let's have a look and we can see Mario Arts the wet Ninja code at UK so it's only replaced the first n right here so that's what this replace function does when we just pass it in a simple string like this it replaces the first one it comes
to with this we can use this with regular expressions to do Something a little bit different but since we've not touched on those yet we'll leave that for later now there are some other string methods that I do want to show you but we're going to be looking at those as we carry on through the course ok then so now we've seen strings in more detail let's shift our focus now to another data typing JavaScript that is numbers so we have also briefly seen numbers in action when we looked at variables we did things Like
storing age or a year or a score in a variable and they were all numbers weren't they now we could use numbers for various things in JavaScript like an age or a school or how many up votes a blog post might have for example or to perform some kind of calculation so there's loads of uses for numbers in JavaScript so let's have a look at them in action first of all I'm going to create two variables I'm going to use the Lett for the first one and this is Called radius and that's set equal to
10 now I'm going to create a constant called pi because I don't see myself changing this I don't want to change it it's a constant and that is 3.14 so pi is a special value in maths used to calculate the area of a circle and the radius is just the radius of the circle so we have those two variables which are both numbers let's just unlock them to the console so we'll say console dot log and then we want the radius and also PI So let's save that and see if it works there we go
10 and 3.14 so these are both numbers this is a whole number this is a decimal number but they're still both numbers the same data type in JavaScript okay so then what can we do with numbers well we can do all the typical math operations so let me just write these down first of all math operators and that is a plus - multiplication which is an Asterix a Division which is a forward slash then we have double asterisks which means ^ and then we have percentage which gets as a remainder so let's have a look
at some of these first of all I'm gonna console dot log and I'm just gonna say ten divided by two okay now we don't need these spaces that I've just put in there I've done that so it's easier to see and this should get us five right and it does it performs that calculation and then spits out the result so that's Pretty simple now what if we do something like this I'm going to say let result equal to the radius which we have at the top it's ten and I'm going to use the percentage three
so what this does is get us the remainder of a calculation it takes the radius divide it by three and then gives us the remainder which should be one so let's log this to the console console dot log and we want to log out the results variable that we just created right here which is storing The result of this calculation it should be one that is the remainder and it is one cool okay so now let me comment this out and in fact I'll comment this one out as well unless do another this time we'll
say let's results equal to the PI which is 3.14 times the radius to the power of two so that is the formula for working out the area of a circle so saying the result is PI R squared this is the square bit to the power of two okay so It's the radius times the radius so let's save that and we'll log it out the result and this is the area three one four which makes sense okay cool so that's some simple examples now I want to talk about something that you probably already know about but
just in case you don't I'm going to go through it and that is the order of operation now this is something you might learn about in school at some point and it just dictates how we perform Calculations when they get a bit more complex the order of operation in what order we do these bits of the calculation first so you might have heard of this big mass let me just type this out and this is the idea we perform the calculation said first of all we do any brackets then any indices which are these things
there then any division then multiplication then addition then subtraction so say for example we had Some kind of complex formula which is something like this we'll say let results equal to and we'll say five times and then in brackets ten minus three and then we'll do to the power of two so it's not over the complex but this right here dictates in what order we perform this calculation so first of all be brackets we perform the bracket calculation so 10 minus 3 is 7 then indices which is this so then we square it so 7
squared is 49 then Division well we don't have it then multiplication which is this thing over here so we say 5 times 49 which is 245 so that should be the result so let's log this to the console and see if we're right 2 4 5 cool now let me just comment this out and what I'm going to do now is create a new variable and we'll say let likes equal to 10 now imagine this is the number of likes a particular blog has now what if we wanted to add 1 to this likes variable
well we could do Something like this we could say likes is now equal to likes plus 1 and if we log out likes console dot log likes then we should see 11 right so we do 11 but there is a shorthand version of this in JavaScript an easier way to do this is by saying likes plus plus and that adds 1 to the likes so if I comment out the first one then this will run and it would still add 1 to the like so we should still see 11 and we do so that is
a shorthand operation there double plus And it's the same as adding 1 like this now the same can be done for - inga like so if I comment this out I could say likes - - and that takes 1 so it should be 9 and we get 9 cool now what if we wanted to add 10 well we could do the same think up here we could see likes is equal to likes plus 10 this time but an easier way to short hand way is by saying likes is plus equal to 10 so what that
does plus equal is take the current Value and add on this value so it's going to take the 10 and add on 10 and if we console out the like so console dot log likes save it and we do that's wise now so let's delete one of them we should see this in the console we see 20 cool and the same is true for other things like minus or times or divide so let's do some other examples I'm going to comment this out and this time I'm going to say likes and minus equals 5 so
it takes 5 away from it so let's save That and we get 5 left that's right I'm also going to do a couple more examples so we'll say likes and we'll say x equals 2 so that is going to take this value and times it by 2 which is 20 and we get 20 and then final it let's do divide so we'll say likes divide equals 2 and that takes the value 10 and divide it by 2 so we should be left with 5 and we are cool so this here this is all shorthand notation
it's stuff we can do the long Wait like this we say likes equals 2 likes times 2 or plus 2 or whatever but this is the quicker way of doing it right here and when it's just 1 we can use plus plus and minus minus okay so that's going to speed things up when we're doing little calculations in the future all right so just a couple more things I want to talk about first of all is not a number or none for short so it looks something like this and a n stands for not a
number and we get this value When we try to do something that doesn't make sense some kind of calculation that doesn't result in a number for example if I log to the console 5 over hello that just doesn't make any sense whatsoever right we can't do that in real life and if we do that in JavaScript we'd get none or n a n it's not a number and we can do something else we could say console the log and we'll say five times hello and log this to the console and we get not a Number
surprise surprise okay so that's one little thing if you get that it means you've tried to do some kind of calculation that doesn't result in a number and you've probably made some kind of error along the way okay now the final thing I'd like to show you is how to concatenate numbers so you know like we said with strings we can concatenate them with a plus sign well we can do a similar thing with numbers if we're trying to add some kind of number into a String we can do that so let me give you
an example I'm gonna say let result equal to the blog has and then a space and I'm going to concatenate this with a number this thing right here likes so plus likes then I'll concatenate with another string space likes so this should say the blog has ten likes and it should result in each string so it takes the ten and it adds it into the string and it creates one big gigantic string well not gigantic but you get the point One big string based on all this so if I now say console.log the results we
should get that let me have you in a browser the blog has ten likes okay now this is fine but if we were to do this with a few different numbers and we had quite a big string then this would quickly get pretty messy when we're trying to concatenate too many variables with a string now fortunately there is a new way to do this using template strings and we're going to see that in The very next video ok then so in this video I don't want to introduce another data type I want to take a
sidestep and talk about a slightly different version of a string and that is a template string and what a template string lets us do is inject variables into the string without having to exit out and using the plus sign to concatenate them so what I've done is create three variables right here a title author and likes they represent a blog post and What I'd like to do is create one big string we which contains all of these different variables at some point now I'm going to show you the concatenation way and the template string way
and you can decide which one you prefer I much prefer the template string way by the way another name for these template strings is a template literal okay so first of all let's do the concatenation way so I'm going to create a variable Called result and set it equal to a string now to begin with it's going to say the blog called and then we need to exit out of the string so you can catenate the title so plus title then back into a string and we'll say by then out of the string and we'll
say the author and then back into the string and we'll say has and then out of the string we want the likes and then finally plus likes like so I'm just going to press control B and that hides the tree over Here for us so we have more room and now this is a gigantic string containing all of these different variables the blog called title which is this by author which is mario has 30 likes okay so know is how many times we have to come out of the string to concatenate something then back into
the string then out then in then out etc this is very very messy but it still gets the job done if I say console dot log and then results we should still see this in the console Correctly the blog called BES reads of two or one nine by mario has 30 likes so this works fine it just looks a bit messy and it's hard to maintain so then let's have a look at the template string way remember the job of a template string is to allow us to inject variables directly into the string without coming
out of it and having to concatenate with plus signs like this so again we'll say let results equal something now this time we don't use Single quotes we don't use double quotes we use backticks and on a standard keyboard that should be in the top left below the escape button and then looks something like this right here okay little backticks so this is how we create a template string just like we create a normal string using normal quotes like this a template string is created using backticks okay so then inside here we can say something
like the blog called And I'm just gonna put title here we'll come back to this and we'll say by author again we'll come back to that has likes likes okay so what we really want to do is replace these things right here in capitals with the actual variables now previously we had to come out with a string and use the plus sign to concatenate them but in a template string to output a variable all we do is dollar sign and then curly braces open and close and then we put the name of The variable inside
those curly braces so for example title and it should have a different color now we'll do the same with author so dollar curly braces and then author which is the name of the next variable then likes so let's do dollar sign curly braces likes and this should all work and I think that looks a lot better we don't have to come out of the string and concatenate anything we just embed the variables directly using this kind of syntax and it reads a lot Better too so let me now consult log the results to the browser
and save it and we get exactly the same result this don't works so I much prefer this way especially when there's many different variables if it was just one variable and it looks something like this first bit concatenation is absolutely fine and I might do that in the future for something like this but when we have a lot of variables and definitely going to be using it template strings now then a Good use case for template strings is to create HTML templates so say for example we have some kind of dynamic content that we got
back from a database and we want to create an HTML template with that content embedded inside it then output it to the browser somewhere well we could use a template string for this so we could say something like let HTML equal to backticks this is a template string and then what I'm going to do is enter onto a new line now then I'm going To just create some h2 I'm going to say h2 and then I'm going to output the title inside the h2 for the blog so we'll do our dollar sign curly-braces then close
off the h2 underneath that we'll do AP tag and inside the P tag we want to say bye and then the author so we'll output that and then close off the P tag and then finally underneath that we can say spun on inside here will say this blog has and then we want to output the likes so Dollar kill de bracy's likes and then likes and then close off oops it's a span tag like so now that if we were to log this to the console we should see all of that HT mastering so if
I save it and preview over here in a browser we can see this HTML string now and we've created that pretty easily using this template string and injecting this dynamic content okay so later on what I'm going to show you how to do is take something like a template like this and Output it to the browser somewhere for now we'll just use the console but later we'll see how to output it to the browser but this is just one use case of using template strings okay they're my friends so far we've seen two different data
types numbers and strings now I'd like to talk about arrays which aren't a new data type in themselves they fall under the object data type right here okay so we typically use arrays to store collections of things in like a Collection of strings or a collection of numbers something like that so let's do a few different examples I'm going to create a variable called ninjas and I'm going to set it equal to a new array and the way we do this is by using square brackets okay this is array syntax now inside this array I
want to have maybe three different strings three different names that are all ninjas so I could create the first one I'll say Shan then I want To add another so I do a comma and I say Ryu then another so I say comma and then suddenly now I don't need a comma after the last one but if I wanted to add another I just come and separate them all like that so that they're my friends is an array with three elements or three values inside it we've stored all of those three values inside one single
variable so you can probably see already why these are useful for storing collections of data that relate to each Other okay so let's see what happens if we log this to the console console dot log ninja's okay save that and view it and we can see this right here this array cool alright then so what if we wanted to get just one of these items well we could use square bracket notation so I could say number one inside and we did this kind of thing with strings when we wanted to get the first position in
a string or the seventh position in a string this is me Saying I want to get the first position in the array and by first I don't mean the actual first I mean position one because remember javascript is a zero-based language we start at 0 then 1 then 2 and so forth so this right here is saying get the second element so 0 1 it should be right so if we save this we should see Ryu in the console which we do cool now that what if I wanted to maybe override one of these positions
say I want to Override position 1 with a new value well I could say something like ninjas and then position 1 the same way we get that value but this time I'm going to set it equal to something new I'm going to set it equal to Ken so save this and this time when we log it to the console it should be can and not right so that's how we override certain values in different positions inside the array ok cool let's do another example I'm going to create a new array this one is going To
be called ages and set this equal to 20 25 30 and 35 ok so we have this array of Ages now what I'd like to do is just output the third position so that would be position 2 so we'll say console.log and we'll set ages and position 2 this should be 30 save it and we can see that right there so I just created this to show you that we can store different data types insider ease these are numbers these are strings were not limited to storing one particular type Of data and if we wanted
to we could mix it up a little bit we could say something like this we could say let's random equal to short for the first element then we'll do crystal for the second element then for the third element we'll say 30 then 20 so we're storing two different types inside the same array now that might not make much sense because I think arrays should store data which belongs together and these don't really belong together but We can still do it there's nothing wrong with doing it so let's log this to the console random this will
absolutely work and we see that array right here okay now arrays like strings and like numbers they have properties and methods so let's have a look at some of those I'm going to comment this out and I'm going to comment this out as well in fact let's have a look at the length property so let's say console dot log and we'll say ninja's dot length like so and long Behold this is going to output three because it counts how many elements are inside that array and it counts that that is the length of an array
how many elements are inside it okay cool so let's move on to some of the array methods so I'm just gonna do another comment down here that says array methods and underneath I'm going to do a few different methods so first of all let result equal to ninjas and what I'm going to do is use a method called join And I'm going to join with a comma so what this does is take an array ninjas in this case and it joins all the elements inside them into a single string and it joins them with a
comma so after every individual element inside the string we're going to get a comma so let me save this preview oops we need to log it to the console first of all console dot log the results save it preview and we can see the string now is joined all of the elements together with A comma in between them if I changed this to something like a - or - then it's going to change this - as well now this - it was already part of the name so don't get confused there it's only these two
hyphens which we've added when we've joined them together in a string so that's the first method now let me show you another one again I'm going to say let's results equal to something this time ninjas dots index off and then we're Going to pass in one of the values so if I pass in children late for example it's going to get me the index of this value inside the array so again and login the results of the console if I save it we can see number two that is the index zero one to make sense
okay cool so that's another method let's do another or say let results equal two ninjas and we're going to use the method called can cat and what can cat does is take our array and it concatenate another array With it okay so if we want to join two arrays together we use the concatenation is joining things together so I'm taking this array and we're going to concatenate it with a new array which we pass through as an argument to this method so just pass an array directly into this method and in here we'll do two
different values can and we'll do crystal like so and we're logging the result to the console so it should be this concatenated with this array right Here in one big array so let's see yet we can see that we have five elements inside this array now all here cool okay so another method we can use is the push method so let me say let results equal two ninjas dot push and what the push method does is push on a new value onto the array right here okay so I'm going to push on a new value
Ken and save this so if I save it like that and look over here we can see we get four back now what this method does is return the Length of the new array okay so when we're logging it to the console it's logging the new length and since we've just added one it will be for now because it was three before but if now we log out ninjas instead and save it we can see we now have four and so you know before when I said that some methods don't alter the original value well
some methods do and this is one of them it alters the original value and for that Reason we call it a destructive method it doesn't really destroy it but it changes it okay so then we can also do something called ninjas dot pop so I'm going to say let results equal two ninjas dot pop and again this is destructive it changes the original value and what pop does is take off the end value so it just added Ken on but now we're taking it back off so when we output it we should just get the
original array save it and we get result Has already been defined so we'll just take off let's save it and we can see now we get the original array because we popped off Ken now what this method does right here is return the value it popped off the array so if I output now results we should get Ken because that's the value that was last in the array that we then pop off and it returns that value so let's have a look and voila we get Ken so there we go my friends that's the basics
of arrays we'll be using them a Lot later in the course when we start to work with data collections and loops to output templates to the browser all right then gang so we've taken a look at numbers strings and also arrays now I want to turn our focus to null and undefined now these two types are quite similar in that they both represent a complete lack of value the only difference is that null is an intentional lack of value but undefined isn't now that might seem a bit odd when I'm talking about it and how
but you'll see exactly what I mean in a minute so let's do a few examples first of all I'm gonna create a new variable and I'm gonna call that age now I'm not gonna set it equal to anything and just kind of setting this variable up but not a sign and get a value yet now what I'm going to do below is console dot three things first of all the age variable then age plus three then I'm gonna output a template string to say The age is and then we'll output the age inside that template
string okay so what I'm gonna do is save this and just run it in the browser over here and we can see for the first value undefined now it's undefined because we've not given it value yet okay so that's what happens when we don't give something of value and we try to use it the browser automatically assigns a value of undefined it's not intentional we've not intentionally said let age be equal to Undefined the browser automatically gives it that value when it doesn't have one now that when we try to use undefined in a formula
like this we get not a number and the third one when we try to output undefined as a variable inside a template string we see this the age is undefined so we get one defined in the string itself okay so that's one defined the browser is automatically giving the variable this value because it doesn't yet have one now I said that Null was an intentional luck of value and by that I mean we explicitly say age is equal to null so we're giving it this empty value of null now okay we didn't do that with
undefined just not so if I save this now and preview in a browser now we can see note for the first one when we try to add three to null we get three so when we output null has a value in some kind of formula it takes on the value of zero and when we try to output it in a string it just becomes null Inside the string okay so that's null and undefined now I said that null is an intentional value meaning that we explicitly assign it a value of no but what's the point
in this why would we ever really want to do this well an example could be that we have say a formula website which asks for a user's title now when they select the title for example miss on misses on mister we store that value in some kind of variable now if at some point the User goes through the rest of the form but then decides to clear the form reset it by pressing a button it all the farm fields at that point we no longer want to store the value of what they selected for the
title for example miss we want to clear it so at that point we could explicitly say well okay now the variable title is equal to null okay so that's null and that's one defined they will be popping up in other watches as we go forward All right then gang so we've taken a look at quite a lot of different data types in JavaScript so far numbers strings no undefined and also arrays which is a type of object now I want to talk about boolean now boolean's represent two special values in JavaScript true and false so
let's have a look at those so the first thing I'm going to do is consult log true and false now these are not strings look right here we've not put them in quotes And they're purple they're colorized by the text editor because it knows that these are special values they are billions so if I save this and see in the console over here we can see true and false now if I put these next to actual strings true and false these are not the same things this is a string which just says true and this
is a string that says false they are not the same as these two things that are not strings so when we view them in a Console the console helps us out and it colors these a little differently from strings so we use boolean's to evaluate conditions in our code and to check whether certain things are true or false for example we can perform some methods on strings or arrays on numbers that are going to return towards a true or false value a boolean so let's do a few examples of this I'm first of all going
to say let's email equal to Luigi at the net ninja code at UK okay so now I'm Going to use a few different methods on this email thing so I'm first going to say let results equal to email that includes and then we're going to look for the @ symbol so this method right here includes we can use on a string to look if a certain character appears in that string now if it includes that character in the string this is going to return true if it doesn't it returns false so it returns a boolean
either way let me lock this to The console I'm going to log the result like so save it and preview and we can see true because it does include that symbol right here if I instead do an exclamation mark it's going to return false because it doesn't include that in the string all right okay so now let me create a new variable called names set that equal to an array and we'll put Mario in there and Luigi and also toad okay so we have this array of names I'm going to come down here and use
exactly The same method on this array so I'm going to say let results this time equal to names dot includes and we're going to look for a particular value inside this array so I'm gonna look for the Ouija now this should be true because Luigi is an element inside this array okay so when we use this method on an array instead of a string it looks inside the array and tries to match this value to one of the values inside the array now we have to comment this out because we Don't want to define results
Wiese save it and preview and we get true because Luigi is inside that array if I change this to something like bowser then it should be false because bowser is not inside the array okay all right cool so let me comment this out again and this one and now what I'd like to do is show you some different comparison operators so we'd use comparison operators to compare two things together and they're going to return a boolean true or false So let's just go through a few examples I'm going to create an age variable first of
all and set that equal to 25 and then I'm going to log something to the console so we'll say console dot log and inside I'm going to say age is equal and that's double equals 225 now notice we're using double equals and not single equals right here single equals sets of value to something like this and when I use double equals what doing is sane are these two things the Same is age equal to 25 so if age is equal to 25 then this is going to evaluate to true and we're going to get that
true boolean log to the console so let me save it and preview and we see true right here cool so what I'm going to do now is just duplicate these onto a new line and we're going to just change the condition inside here so now I'm going to change this to 30 is age equal to 30 now that's false so we should see false over Here and we do now let's do another so I'm going to say is age now I'm going to replace the first equal sign with an exclamation and what this does is
negate this so it says is age not equal to 30 okay now age is not equal to 30 so that's going to be true this statement if I change this to 25 then age not equal to 25 that would be false because age is equal to 25 that's a little difficult to get your head around at first but just remember this right here This turns it into a not equal so if these things are not equal then the statement is true so if I save it then we should see true because age is not equal
to 25 that statement is true okay so next one let's just duplicate this again and I'm gonna say now age is going to be greater than 20 so the greater than sign is that right Chevron and in our case this is going to be true because age is 25 which is over 20 so let's save it and we get true let me Duplicate this and change this to less than and in this case we're going to get false because age is not less than 20 because it's 25 okay all right so just a couple more
the next one is going to be less than or equal to and I'm going to change this to 25 so when we add an equal sign after the Chevron no matter whether it's greater than or less than then this turns it into less than or equal to 25 now this is going to be true because it is 25 is Less than 25 but this says less than or equal to so that should be true and we get true over here okay one more let's just do the opposite of this we're going to say greater than
or equal to 25 and save that and this statement is true as well cool okay so there are load of different comparison operators we can use right here for comparing numbers and we're going to do that quite frequently later on and they all return boolean's now I'm going to do The same kind of thing but this time I'm gonna do it with a string so I'm going to create a new variable called name and set it equal to Shaun obviously and then I'm gonna come down here and say console dot log and we're going to
do a very similar thing I'm gonna say that name is equal to remember double equals short now is that the case well yeah this is Shaun so this statement right here this should be true so I'm gonna save it and we see true Okay let's do a few more examples we'll say name is equal to Shaun with a capital S now what do you think well this string is not equal to this is it even though it's the same word we have a capital letter here and those two things are different in JavaScript so if
I save it now we should see false okay okay let's do another example I'm gonna say name is now greater than crystal now how does this work with strings well first of all if we save it and preview We can see that this is true so it's saying that Shawn is greater than crystal and that's the case because the first letter right here s comes later in the alphabet than C now when that's the case it's greater than it so later letters in the alphabet are greater than earlier letters in the alphabet all right so
what if we added some kind of capital letter to the mix I'm going to change this to Shawn but we're still doing it greater than now is this shot Going to be greater than this Shawn well let's save it and find out this is true so again when we have a lowercase letter that is greater than an uppercase letter now that might seem counterintuitive at first but that the case in JavaScript lowercase letters are greater than uppercase letters okay so one more example I'm gonna say is Shawn greater than crystal with a capital C and
I'm gonna save it and preview it and true again so not only is The small case s greater than its counterpart the big case s it's also greater than any uppercase letter so all of these kinds of comparisons are going to be really useful to us later on when we start to check if certain conditions are true or false and then execute some code depending on the result of a comparison so for example is a user logged in if that's true then I'm going to execute some code to show you use the dashboard in the
browser if it's not Then it won't now so far when we've compared two things together to see they're equal we've used double equals right here and that is what's known as abstract equality or loose equality which means that a values type is not considered when we perform the comparison and we're going to talk about that more in the next video and how we can use a stricter and better type of comparison for things like this or rather my friends so in the last video We saw that we could compare different things and one of those
comparisons was this equality right here so we use double equals to see if two things were the same so we have a variable age we've set it to 25 and we're checking if that equals 25 now obviously this is going to return true it does now this double equals sign right here this is known as loose comparison meaning that different types can still be equal for example let me do placate this and I'm going to see If age which is the number 25 is now equal to the string 25 so what do you think will
happen let me save that and preview and we get true so javascript is saying these two things are equal even though they're different types and what's happening is behind the scenes javascript is a look at at this comparison and it's converting this string into a number the same type as this before it evaluates it okay so when we compare two things to each other Using a double equal signs then different types can still be equal because of this type conversion that JavaScript does in the background so let me just do another couple of examples I'm
going to comment out the first two here and then up here I'm going to replace these with not equals and not equals and I'm going to make this a number 25 and this is string 25 so we're saying here age is not equal to 25 now that would be false because age is 25 And we're saying here age is not equal to the string 25 but remember the string is converted into a number first of all so behind the scenes it's still the same thing as this so this should be false as well so let
me save that and preview and we get two falses okay so that's fine we can do this loose comparison using two equal signs but it's not always the most accurate way of checking something so most of the time I think it's better to use what's known as strict equality and We do this by instead of using two equal signs here we use three and instead of one here we use two so let's do a few examples I'm going to come down here and I'm gonna say console dot log age is triple equals 225 now this
right here this triple equals this is strict comparison so we're saying is age the same value and type two this okay 25 well yeah in this case it is so we should get true which we do but if I do another example now and change this to a String 25 then now this should be false because we're checking the type as well and 25 the number is not equal to 25 the string there's no type conversion going on behind the scenes javascript isn't taking this string and converting it into a number before comparing them instead
we're comparing the number with the string directly and they are not equal so if we save this then we see false because really a number can't be equal to a string okay two more examples This time I'm gonna change this to exclamation mark double equals and exclamation mark double equals we'll change this to a number right here as well 25 so whereas before we had and then what equals now we have that and then - so this is a strict comparison again it's taken into consideration now the type and not doing any type conversion behind
the scenes so is age not equal to 25 well that should be false because age is equal to 25 but Is age not equal to the string 25 well that's true because we're using strict comparison now and this is not equal to this okay so let's save it and preview and we can see false and then true so false and true just what we expected so most of the time it's better to use strict comparison because it results in more predictable results and probably 99% of the time that's what I'm gonna be using going forward
okay then so we've seen Quite a lot of different types so far now I'd like to touch on something called type conversion and that basically means turning one data type into another data type and you might want to do this sometimes for example we've got a variable here called score and we've said equal to 100 but the string 100 now imagine we wanted to perform some math with that value we wanted to add one to the score for example which would be a hundred and one Now if that's a string and we try to add
one then this is not going to work we're going to get concatenation whereby the number here is added on to the end so it becomes one thousand and one so we're not adding one to the value so it would be nice if we could convert this string into a number type and then perform the calculation that is type conversion so then let me do this what I'm going to do is grab the score value and we're going to update it by turning it into a number And the way we do that is by saying number
capital n and then in brackets we pass in the variable that we want to turn into a number which is the score so now we're saying the score is equal to the number of the score and that takes this string and it turns it into a number and that number would be 100 so now when we try to add one to the score because it's a number now we've converted it now it should be 101 so let's test that out now Get 101 cool okay so that's a simple type conversion and by the way you
can check the type of something by using the type of operator so let me just do that console dot log and I'm going to say type off all one word then a space then the variable that we want to check the type off so we want to check the type of score I'm going to save that and we're going to see that this is a number now if I just comment out this line so we're not turning it into a number then it Should be string because originally it was a string up here okay okay
cool so let's move on now what if we have a new variable called results and we want to set that equal to a string what if we want to try converting this into a number well that doesn't really make sense does it let's try it so number and then we pass in the value that we want to turn into a number I'm gonna log down here the result like so and save it so if we come Over here we can see now not a number so if we try to take something that doesn't really make
sense to turning to a number and try to use this right here to turn it into a number then we're gonna get not a number as a result okay all right then so let's try it the other way around what if we want to take a number and turn it into a string well let's say let result equal to this time string with the capital S and then we're going to pass in a number I'm going to pass in 50 and I'm gonna save it and come over here and we can see 50 now how
do we know that this is actually a string and not a number well first of all when we type in a number in the console it comes out as blue but that's shady logic we can use the type of operator down here we can say type off and then we'll put the result there so every time we do some kind of conversion we're outputting the result and the type of that result variable so if I save we can see that 50 And string and that's what we wanted to do we wanted to take this and
convert it into a string right okay so let's move almost do another example we can also convert things into boolean's remember billions and those things true or false so we could say let result equal to boolean and then passing something like 100 now what do you think this is going to do well if I save this and come over here we get true and the type is boolean so When we do these type of conversion in JavaScript when we try to make something into a boolean some values are considered true and others false now you
might hear them being called true thick or false it values and this right here this 100 this is a truth a value but if I try 0 and save it then we get false so 0 is a false it value okay so positive numbers are considered a true T value in type conversion - numbers are also truth it but 0 is false Ok now let's do another example I'm going to come down here and say again let results this time equal to a boolean and it's going to be the string 0 so what's this gonna
be we know that this is a false value normal serial but what about a string of 0 well let's come over here we can see this time it's true now strings of any length they are all truth it but if we make it an empty string of no length then this would be false it okay we can See false now so this is all explicit type conversion meaning we've explicitly tried to convert the types right now there's also something called implicit type conversion which JavaScript does behind the scene we saw that in the last video
when we talked about loose comparison JavaScript changed the type of our values behind the scene before comparing them and that will come into play in other areas too in the future for now though it's enough just to Understand that we can convert types either ourselves explicitly like this or implicitly behind the scene
