Strings, Numbers, and Boolean Data Types

Quick reference

• 00:05 In this video, I wanna talk about strings, numbers, and Boolean data types.
• 00:09 So, we've already played around with strings.
• 00:11 That's just var myName = John Elder.
• 00:17 That's a string.
• 00:18 And we've already looked at numbers var myNum = 41.
• 00:24 I'll talk about them a little bit more in this video, but
• 00:27 I also wanna talk about Boolean data types.
• 00:29 And that maybe something that you haven't heard before.
• 00:31 So strings, numbers and Booleans are all types of data.
• 00:34 These are all data types, right?
• 00:36 And knowing what kind of data type they are and
• 00:38 what you can do with that specific data type is important.
• 00:41 For instance, you can add two numbers, but you can't add two strings, right?
• 00:46 We've already sort of talked about this.
• 00:47 You also can't add a string to a number, but let's go ahead and try.
• 00:51 So if we wanna to come back here and do document.write and
• 00:58 then add myName + myNum.
• 01:02 So what do we think is gonna happen here?
• 01:04 You can't, what's 41 plus John Elder?
• 01:07 So if we come back here, it smushes these together, and
• 01:10 it just turns them into a string, right?
• 01:12 So that's kind of interesting.
• 01:13 So what happens if we try to add two strings?
• 01:17 So let's go, Is Awesome.
• 01:20 So if we save this,
• 01:20 what is John Elder + Is Awesome, likewise it just smushes these two together.
• 01:25 And you could see there's no space in between them or anything.
• 01:28 And one little trick you can do if you wanna put these things together,
• 01:31 you can a space to one of them and it kinda does that.
• 01:33 But that's just sort of a hacky little thing.
• 01:35 It doesn't have anything to do with what we're doing here.
• 01:37 Likewise, earlier, remember we had myNum 41.
• 01:43 If we change this string to 2.
• 01:48 If we save this, this is not a number.
• 01:50 Remember I mentioned earlier it's got quotation marks around it, so
• 01:53 it's still a string, but it looks like a number.
• 01:55 So what happens here, same thing It just smushes the two together,
• 01:58 turns it into a string.
• 02:00 So that's kinda fun, but what exactly is a Boolean?
• 02:02 A Boolean and that's just in case you're wondering, B-o-o-l-e-a-n.
• 02:09 A Boolean just means true or false.
• 02:11 We often use Boolean when we compare things we've just talked about comparison
• 02:15 operators and we were actually using Boolean back then.
• 02:18 I just didn't really call them that 'cause we were trying to decide is two equal to two?
• 02:22 Yes, it is that's true.
• 02:24 True is Boolean.
• 02:25 Not only do we use it to sort of determine if a thing is true or
• 02:28 false but we can also make a variable into a Boolean.
• 02:32 So we can go var myVariable = true, right?
• 02:37 So now the variable, myVariable is true likewise we can call it false.
• 02:43 You'll learn more about Boolean later on when we start doing if statements and
• 02:46 loops and things like that.
• 02:47 But often it's useful to test if the thing is true or not and
• 02:50 we will do that when we will use Booleans.
• 02:52 So that's strings, that's numbers, that's Booleans,
• 02:55 those are data types we will look at some of them later on in the course.
• 02:58 So, in the next video we will look at arrays.

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