Rules for Naming Variables

Follow these rules when naming variables:

• A variable name must be of the form $name or ${name}.
• The string name can consist of letters (a-z and A-Z), numbers (0-9), and underscore characters (_).
• The first character of name must be an alphabetic character (a-z or A-Z).
• If the ${name} form is used, spaces can also appear in name. This allows you to use multiple word names without the underscore character.
• C language is case sensitive so best practice is have lower case of variable names.
• Reserved names can’t be variables.