When you write a program, you work with information that generally falls into one of five basic types: integers, real numbers, characters and strings, Boolean expressions, and pointers.

Integers are whole numbers (1, 5, -21, and 752, for example).

Real numbers have fractional portions (3.14159) and exponents (2.579x1024). These are also known as floating-point numbers.

Characters are letters of the alphabet, symbols, and the numbers 0-9. They

('This is only a test.').

Boolean expressions have one of two possible values: True or False. They are used in conditional expressions, which are discussed later.

Pointers hold the addresses of locations in the computer's memory, which in turn hold information.

See Also