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Instructor: Welcome back.

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Let's talk about our first data type.

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And you know what?

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Let's do two at the same time.

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We have int and floats.

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Int stands for integer, as you can see here,

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and float stands for a floating point number.

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Hmm.

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Let's explore that.

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First, let's start off with integer.

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An integer is, well, a number.

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Three or four or five, these are all integers.

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In a programming language,

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you can use integers to do mathematical operations,

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for example 2 + 4.

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If I run this, well, nothing gets printed

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because, again, we have to perform some action

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on these data types.

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And one action that we've learned so far

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is this idea of printing.

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And we print something

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by calling the print keyword with the brackets.

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So the brackets is almost like saying,

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"Hey, perform this action on these data types."

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And if we run this,

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we get six right here.

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Awesome.

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So, not only are we using print,

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but we're also using the plus sign to perform an action,

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to add the two data types together.

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And as you can imagine,

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we can do most mathematical operations, the basic ones.

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We can do negative.

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We can do, let's say 2 times 4,

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and then we can also do 2 divided by 4.

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And if click run here,

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all right, it looks like everything is working.

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We've added, we've subtracted, we've multiplied,

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and then we've also divided.

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Now, here's the interesting part.

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Up until now, we've used what we call integers.

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That is, these are whole numbers.

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There's no decimal places, they're just, well, integers.

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And a neat trick that I can do here is I can actually say,

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"Hey, what's the type of 2 plus 4?"

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If I click run here,

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all right, let's decipher what just happened.

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I've taught you another action that we can perform

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which is something called type

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which tells us, "Hey, what data type is this?"

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And just like in math, we go bracket by bracket.

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So the first part, Python says,

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"Hey, what's 2 plus 4?

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Well, that's going to be six."

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And it's going to say,

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"Hey, what's the type of six?"

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Well, the type of six, that's an integer.

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So it's going to say class int.

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We don't have to worry about the class keyword for now.

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That's something that we'll talk about later.

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But we see here that we're using int for integer.

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And then finally, after this gets evaluated by Python,

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we print out whatever this does, which is class in.

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Now, check this out.

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Let's do the same for all these ones as well.

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So we're gonna say, type here, type here,

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and then type here.

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And if this syntax is intimidating, don't worry.

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This is something that you get used to.

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If this is your first programming language,

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it is not going to be easy because well, if it was easy

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then everybody would be doing it.

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So hang in there.

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Trust me, as you practice more

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this is going to start making more and more sense.

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Now, before I click run,

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what do you think the output of each one of these lines are?

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Ready? Give it a guess and let's click run.

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All right, we got int.

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For six, we have negative two here,

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which is also an integer.

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We have eight here, which again, is also an integer.

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But then we have float.

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Because two divided by four is 0.5.

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Hmm, what is that?

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Well, remember we are talking about two data types here.

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We're talking about int and float.

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And float is what we call a floating point number.

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A floating point number is simply a number

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with a decimal point.

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In our case, this is 0.5, so it's a floating point number.

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So if we write a number,

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let's say we'll do print, type,

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and then I'll say 0.00001.

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What do you think we'll get?

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Well, we would get a float.

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If I do 5.0001, again, we'll get a float.

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What about the number zero?

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If I click run,

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I get an int because, well, there's no decimal points.

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Why do we need to make this distinction in programming

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and specifically in Python?

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Well, it's because a float

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takes up actually a lot more space in memory

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than an integer, right?

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Because, remember, this number, the number six,

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this needs to get stored in memory on our machine.

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And remember that machines don't really understand this.

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They understand zeros and one.

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And they store this number

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in something called a binary or binary numbers

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which is zeros and ones.

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Now, the problem is when you have decimal places

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like zero point, or let's do 10.56,

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it's hard to represent that

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in a binary number, zeros and ones because of this point.

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So a floating point number essentially stores these numbers

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in two different location, one for the 10 and one for 56.

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Now, we don't need to get technical here

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but that's the idea.

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The idea is that we need more memory

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to store a number like this

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than a number like this.

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Now, the topic of floating point numbers is really,

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really interesting, and I'll link to a resource.

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But the best way to learn more about floating points,

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again, it's not super important

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that you know the technical details,

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but if you go to floating point number Python.

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Again, you wanna make sure

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that you go to the documentation for version three.

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And you can actually learn

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about floating point arithmetic.

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And these official documentation by Python

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are always a good tool for you to use

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whenever you get confused about something

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or you wanna get a little bit more extra detail.

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But let's get back to the topic at hand.

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Both int and float are used for well numbers, right?

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And, Python is going to automatically format the type

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to whatever well, makes sense.

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For example, if in here,

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I do 20 plus 1.1,

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one is a integer,

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the other one is a floating point number.

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But when I click run here,

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automatically Python is going to convert it to float.

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Let's remove these here so that

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we don't get confused by them.

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So if I run this, we see that this whole expression

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is converted into, well, a float.

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Now if I do, let's say 9.9 here,

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which will equal to 11 and I click run,

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these two floats add up to,

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while still a floating point number

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because if I remove the type from here

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and I click run, it gives me the result 11.0.

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It keeps the floating point numbers.

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All right.

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But at the end of the day,

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what we care about is that

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Python works the way we expect it to.

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That is we can do mathematical operations.

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As a matter of fact, we can do a few other things as well.

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There's also this idea of the double multiply.

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So this means to the power of so two

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to the power of two, well, that's going to equal four.

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Two to the power of three is going to equal eight.

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We also have the double divide.

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That is we can do two divided by four.

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But then we use two slashes here.

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If I click run here, I get zero.

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This actually returns an integer.

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Round it down.

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If I do three divided by four, I get zero.

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But if I do five divided by four, I get one.

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This gets rounded down to a integer.

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Finally, the last operator

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that we're gonna learn about is called modulo.

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And it looks something like this.

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If I do five modulo, which is the percent sign.

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Divided by four or modulo four,

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if I run this, I get one.

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Modulo is used to represent

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what's the remainder of this division.

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So if I divide five by four,

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the remainder of this division will be one.

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If I do six divided by four with modulo

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and I run, I get two.

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Two is the remainder of four.

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All right, let's take a break and learn a little bit more

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about these numbers in the next video.

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Bye-bye.