## boolean expressions

You learned before that we can use arithmetic operators to create expressions that evaluate to numbers. For example, `+` is an arithmetic operator, and `3 + 4` evaluates to `7`. You can use comparison operators to create expressions that evaluate to booleans:

``print(4 < 5)``
``````True
``````

`<` is a comparison operator, and `4 < 5` is an expression that evaluates to `True`.

There are several other comparison operators:

``````print(4 < 5)
print(10 > 11)
print(7 == 7)
print(14 >= 5)
print(9 <= 9)
print(1 != 6)
print(1 != 1)``````
``````True
False
True
True
True
True
False
``````

Note that we wrote `7 == 7` instead of `7 = 7`. That’s because we use a single `=` for assigning values to variables, as in `foo = 7`. We call it the assignment operator. The double `==` is a comparison operator. It compares two things and checks if they’re equal.

The last operator, `!=` means “not equal.” It’s the opposite of `==`.

You can store the results of boolean expressions in variables:

``````foo = 5 < 3
print(foo)
bar = 14 == 14
print(bar)``````
``````False
True
``````

Just as the computer evaluates arithmetic expressions, it will evaluate boolean expressions. Consider the following block:

``````a = 3
b = 2 > 4
c = a == 3``````

This will get evaluated like so:

```    a = 3
b = 2 > 4
-> b = False
c = a == 3
-> c = 3 == 3
-> c = True
```

In English, the third line means that `c` will be `True` if the value of `a` is `3`, otherwise `c` will be `False`.

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