Naming variables

Learn valid variable naming rules.

Variable naming rules

A variable name must start with a letter or underscore; it cannot start with a digit. It can contain letters, digits and underscores.

Valid names: user_age, _count, total2. Invalid names: 2nd (starts with a digit), user-age (has a hyphen), class (reserved word).

Python is case sensitive: age and Age are different variables. Reserved words (if, for, class, def) cannot be used.

The Python community convention is to use snake_case: lowercase words separated by underscores.

For boolean variables the is_ or has_ prefix is common. This convention is defined in PEP 8.

Assign "Alex" to user_name, assign 25 to user_age. Then print print(user_name).

Show example solution

user_name = "Alex"
user_age = 25
print(user_name)

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