# Logic Comparisons

Lesson Progress
0% Complete

## Boolean operators

There are three basic boolean operators in Python.

• `and``True` if left and right value are both `True` or both `False`
• `or``True` if either left, right or both are `True`1
• `not` – gives the opposite value of the boolean to the right, i.e. `not True == False`

1 If the first condition is met, then the second condition will not be tested.

### Boolean comparisons

• `==` – equal (not recommended for use with float values)
• `!=` – not equal
• `<` – less than
• `<=` – less than or equal to
• `>` – greater than
• `>=` – greater than or equal to

## If/Else

`if` statements allow one to execute a piece of code only if a certain condition is met.

``````if 3 > 4:
print('Wow, 3 > 4 is True!')``````

In the above example, a `print()` statement is nested (indented underneath) within an `if` statement. It will only run if its boolean test returns `True`. However, as `3 > 4` is a false statement, the `print()` statement will not run.

Conditional logic can also be chained together using `if`, `elif`, and `else` statements (`if`, `else if`, and `else` in other languages).

An `elif` is a type of `if` statement that only runs where the previous `if` or `elif` test was `False`. This provides an opportunity to handle a variety of cases using different chained tests.

Finally, an `else` statement – placed at the end of an `if`/`elif` chain – executes its code where all previous tests have returned `False`. An `else` statement is generally used to catch all cases not handled with earlier logic tests.

Quizzes