Dictionary.net

A number representation scheme where a number,F is represented by an integer I such that F=I*R^-P, where R isthe (assumed) radix of the representation and P is the (fixed)number of digits after the radix point.On computers with no floating-point unit, fixed-pointcalculations are significantly faster than floating-point asall the operations are basically integer operations.Fixed-point representation also has the advantage of havinguniform density, i.e., the smallest resolvable difference ofthe representation is R^-P throughout the representable range,in contrast to floating-point representations.For example, in PL/I, FIXED data has both a precision anda scale-factor (P above). So a number declared as 'FIXEDDECIMAL(7,2)' has a precision of seven and a scale-factor oftwo, indicating five integer and two fractional decimaldigits. The smallest difference between numbers will be 0.01.