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Let's come back a moment
to the boolean data type.

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In this lesson, I'm going
to show you how you can

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make some tests and
get a boolean as a result.

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And this boolean will be the
foundation for using conditions and loops.

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And for this lesson,
I'm going to just use the

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Python shell here to
keep things very simple.

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So first, we have the boolean data
type with true and false as a value.

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Okay, only two values.

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Then what I can do, let's say I want
to test the equality between two values.

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I want to test, so let's
make a very simple test.

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I want to test if one is equal to one.

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And this is true.

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And as you can see, to test the
equality, I use two equal signs, okay?

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Just one equal sign is to assign a value
on the right to a variable on the left.

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With two equal signs, this is
important to make the difference,

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this is going to compare
the value on the left

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and the value on the
right and return a boolean.

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Is this true or is this false?

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Now, if I want to test, let's say
one is equal to two, well, this is false.

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Okay, so that kind of
conditional statements,

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we are going to use that in
the conditions and in the loops.

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Now, let's see what we can do here.

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So we can use integers, okay?

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We can compare two integers.

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We can also compare,
let's see, two is equal to two.

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So 2.0 is equal to 2.0.

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We can also compare float number.

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We can compare strings.

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Okay, hello is equal to hello.

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Now, if I do the same, but let's say I
put an uppercase here, this is false.

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And then, well, we have just seen
the equal equal operator, okay?

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This is just one comparison operator.

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And you have different operators
for different stuff you want to test.

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Now, let's say I want to test not
the equality, but the inequality.

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I want to test if one
is different than two.

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In this case, I'm going to
use exclamation Mark equal.

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And this is true because
one is different than two.

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If I test if one is different
than one, this is false.

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Okay, so that's it for the equality.

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And now what you can
test is you can test if a

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value is, for example,
lower than another value.

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Let's test if one is lower than
two with this angle bracket here.

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And this is true.

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Now, let's test if one is lower than one.

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This is false because
just one angle bracket

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means that it is
strictly lower than this.

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Okay, so one is not
strictly lower than one.

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So this is false.

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Now, I can also test with
the angle bracket and equal.

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And this means lower or equal than one.

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So if I press enter, we have true
because one is lower or equal than one.

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And I can make the opposite or so.

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I can test if it is greater.

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So if one is greater
than two, this is false.

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One is greater or equal than two.

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So this is still false.

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Let's put one and this is true because
one is greater or equal than one.

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Okay, now two is greater than one.

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In this case, that works.

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Okay, so basically you have
six comparison operators.

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The equal equal, the difference
than, and then the strictly

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lower, lower or equal, strictly
greater, and greater are equal.

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Okay.

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And just one last thing I'm
going to show you which is very

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specific to Python is let's
say you have a list, number list.

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I'm going to create a list
with just some numbers.

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Okay, one, two, and four.

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What I can do is I can check if a
value is inside that list very simply.

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I can do, for example, two in number list.

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And this is true.

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So you put first the value and then the
keyword in and then the name of the list.

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So here we test if two is inside that list.

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Yes, because it's here.

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If I try with three in number
list, this is false because

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there is no element that
corresponds to three in the list.

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So that is very specific to
Python and that's something

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that you are going to
use also a lot in the future.