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By now, we have only used round numbers in

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variables, which we can also call integers. But in

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fact, there are more types you can use to

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represent different kinds of data. And let's

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discover them now. And first, I'm going to give

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you another useful Python function, which is named

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type. Okay. So in Python, you have some built in

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functions you can use, okay, and to call a

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function, it's simple. You just write the name of

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the function, and then open and close parentheses

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and in the parentheses, you're going to give any

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parameter you need to give. Sometimes there is no

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parameter, sometimes you have to give parameters.

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So here, let's say I give type 3. So I simply

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put a round number here, inside the type function,

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and this gives us class int. So don't worry about

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the class for now. Okay, just focus here on the int. So

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int for integer, so I have my variable a, which is

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equal to five. If I do type a, okay, I can also

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get type of a variable directly, and you can see

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type integer. So this is the first type, okay, you

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have used and one of the most important. Now let's

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say, type(4.5). This is, as you can see, now it's

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not int anymore, it is float. So this is a float

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number. If I do type(3.0), we also get float. Okay,

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you can see as soon as I add a point to the

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number, even if after this is zero, we get the

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float number. So this is a different datatype

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okay, int and float. And so if I do, let's say e

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is equal to 4.6, and then I do type(e), I get class

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float. So at anytime, you can just use type with

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the name of the variable to see what kind of data

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type you have here. Okay, now let's see, let's say

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do type(4+6). Okay, you can see so 4

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+ 6 will be evaluated to 10. And then 10 will

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be passed to the type function, and this is going

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to give us int. Now if I do type, let's say (4.5+4.3),

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okay, you can see the result is float.

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And if I do type(4.5+3), so here I am

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adding a float number and an int number, and the

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result will be float. So you can see whenever you

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use a float number in an operation, when the

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result is going to be float. So great. We have two

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main datatype for numbers, integers and float

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numbers. Now we're going to see two new other data

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types, which are representing other things than

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numbered. The first one is a Boolean. So if I

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write True, okay, if I write False like this, so

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True with uppercase and False also with

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uppercase, you can see it's working, this is

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working nicely, because those are values you can

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use, okay? Those are Boolean values. So a Boolean

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is simply a data type, which only has two values,

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True or False. And we are going to come back to

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this actually, later when we work on conditions.

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So that will be very useful to create conditions.

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So if I do type

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(True), you can see class bool for Boolean, can also

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type(False) Boolean. Okay, and then the fourth type

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we're going to see here is the string datatype. So

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if I do type("hello"), like this, you can see class,

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str, str for string. And one thing about strings

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is that you can use if you want double quotes or

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single quotes, okay, you can see this is also

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going to give us string. So for now, the

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difference is not that important. I'm just going

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to follow and continue to close with double quotes

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like this. But the important thing is that you

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stay consistent. So if you use double quotes, you

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use double quotes at the end. If you use single

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quotes, you use a single quote at the end, okay,

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if I try to do let's say "hello', like this, I open

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with a double quote, I close with a single quote,

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I'm going to have a SyntaxError, okay? This is

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not going to work. So if I just create a text

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variable, which contains "Hello", for example, and

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then I do type(text), I get class str, and one thing

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that is important is whenever you add quotes to

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actually anything, this is going to become a

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string. Okay. If I add quote to three, this is

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a string Okay. This is not an int number. Okay,

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very important to make difference, okay, you can

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have three, but this can be a string because you

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have put quotes. Same for, let's say 3.0, which

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3.0 is a float number, but this is a string, and

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also type, if I do True like this, this is also a

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string. Okay, and one thing you can do also with

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strings, these, you can use the plus operator.

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So if I do hello, like this plus, let's say,

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world. So I have added the space here. Okay, I

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press Enter, and you can see the result is hello

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world. So this is a specificity of strings.

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Because of course, for a string, it doesn't make

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any sense to kind of multiply two strings, okay.

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But you can use the plus sign to just concatenate

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two different strings and make it just one string,

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and the result will be a string. Okay, so if you

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try to do type on this, you will get also str. And

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this, of course, you can store it inside a

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variable. You could create one variable for this

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one variable for this and create a new variable,

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where you just add the two variables, and you will

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get the same result. So great, you have just

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discovered four Python data types, you're going to

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use in all your future programs, integer, float,

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Boolean, and string. One thing to note here, you

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don't need to manually precise the datatype. When

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you create a variable, the data type will be

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automatically evaluated, depending on the value

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you're assigned to the variable. And one other super

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important thing, try not to change a variable

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datatype after you have created it. So for

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example, let's say I have name, which is equal to

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Ed. Okay, name contains Ed and I can type name,

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okay, this is an str. Now, what I can also do, and

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this is valid in Python, I can just do name is

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equal to two. So no name is to any file type name,

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I got class ints. So the name was before when I

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created name for the first time it was a string

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and now it is an integer. This is a very bad practice,

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don't do that. Okay, you won't get a Python error

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when you just assign a new value with a new type

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to the variable. But this is a sure way to mess

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up with your program and get a lot of errors later

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on. So once you've created the variable stick to

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the same data type for this variable. And because I

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have also previously told you to use meaningful

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names, so let's use a few examples. For example,

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you have the user_age, okay, 45 or 55. You have

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you can use the user_name for example, let's say,

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Bob, okay. And then if you want to float number,

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let's say room_temperature, which is equal to

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34.5. And let's say is_activated which is equal to

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False. Okay, so here you have an example with four

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different variables with four different data types

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and with meaningful names.