Constants are values that do not change. For example, in the expression PRICE * 1.05, the value 1.05 is a constant.

You must enclose character constants in pairs of single (') or double (") quotation marks. To include a single quotation mark in a character constant enclosed by single quotation marks, use two single quotation marks together (for example, 'Don''t'). Similarly, if the constant is enclosed by double quotation marks, use two double quotation marks to include one.

You must enclose date and time constants in braces ({}), for example, {01/30/89} and {12:35:10}. The form for date constants is MM/DD/YY or MM/DD/YYYY. The form for time constants is HH:MM:SS.

The logical constants are .T. and 1 for True and .F. and 0 for False. For portability, use 1 and 0.