--- title: variableNamingBestPractices tags: - python - variables - syntax - naming - constants aliases: - naming conventions - snake_case - ALL_CAPS - variable reassignment --- > [!important] Naming Best Practices > - Use **snake_case** for variables: `user_name`, `email_count` > - Use **ALL_CAPS** for constants: `MAX_CONNECTIONS = 10` > - Python doesn't enforce constants, but the convention is **SCREAMING_SNAKE_CASE** > - Define constants at the **module level** for global visibility > > - Avoid unintentional reassignment. Python allows variable re-binding to different types: > ```python > my_var = 1 > my_var = "Now I'm a string" > ``` > > - Variables don’t auto-update in expressions. You must reassign explicitly: > ```python > bacon = bacon + 1 > # or > bacon += 1 > ``` > > > [!example] Reassignment Example > > ```python > > first_variable = 1 > > first_variable = 2 > > print(type(first_variable)) # > > print(first_variable) # 2 > > > > first_variable = "I'm a string now! I used to be an integer." > > print(type(first_variable)) # > > print(first_variable) > > ``` > > > [!info] Related Notes > > [[variableNamingRules]] > > [[typeConversions]] > > [[pythonSyntaxOverview]]