Boolean

A value that is either True or False.

A boolean (bool) holds one of just two values: True or False. Comparisons such as 5 > 3 evaluate to a boolean, and booleans drive if statements and while loops. Combine them with and, or, and not.

Python also treats other values as "truthy" or "falsy": 0, 0.0, an empty string, an empty list [], and None all count as false inside a condition.

Example
is_open = True
print(5 > 3)            # a comparison produces a boolean
print(is_open and False)
print(not is_open)
print(bool(""))         # an empty string counts as False
Output
True
False
False
False

Where this shows up in real Python

Booleans drive every decision: the condition in an if or while, validating input, and toggling features on or off.

Commonly used Boolean tools

  • and / or / not — combine and invert conditions
  • == != < > <= >= — comparisons that produce True/False
  • any(items) / all(items) — is any/are all of them truthy
  • bool(x) — see how a value is judged truthy or falsy

Related lessons