Identifier name rules

Different programming languages have different rules on how identifiers can be named.

General rules

In most programming languages, you must follow these identifier naming rules:

• The identifier cannot contain spaces
• The identifier can contain only numbers, letters and underscores
• The identifier must not start with a number
• The identifier name must not be the same as a language keyword

Identifier naming conventions

While not rules, most programming languages have conventions you should follow.

There are also good practices to name your identifier as clearly as possible.

See: Identifier naming conventions