Parameter

A variable or notable characteristic. A measurable quantity, such as temperature or pressure, that is essential to the operation or description of a system. The word parameter has slightly different meanings in different fields. For example, in computer programming, it refers to an input variable in a subroutine. It is a variable that must have a specific value to execute a program. In mathematics, it is a constant or variable term in a function that determines the specific form of the function but not its general nature, as in f (x) = ax, where a is only the line’s slope described by f ( x ). In probability analyses families of probability distributions may be identified by the values of their parameters.