Refers to numbers in base 10 (the numbers we use in everyday life). For example, the following are decimal numbers: 9; 100345000; -256 and 3,567, even though none contain a decimal. Note that a decimal number is not necessarily a number with a decimal point in it. Numbers with decimal points (that is, numbers with a fractional part) are called fixed-point or floating-point numbers. In addition to the decimal format, computer data is often represented in binary (base 2), octal (base 8), and hexadecimal (base 16) formats.