| In programming, a variable is a value that can change,
depending on conditions or on information passed to the program. Typically,
a program consists of instructions that tell the computer what to do and
data that the program uses when it is running. The data consists of constants
or fixed values that never change and variable values (which are usually
initialized to "0" or some default value because the actual values
will be supplied by a program's user). Usually, both constants and variables
are defined as certain data types. Each data type prescribes and limits
the form of the data. Examples of data types include: an integer expressed
as a decimal number, or a string of text characters, usually limited in
length. |
