Glosarry >> P >> What is a Parameter

In computer programming, a parameter or a formal argument is a special kind of variable used in a subroutine to refer to one of the pieces of data provided as input to the subroutine. []

A parameter is a named variable passed into a function. Parameter variables are used to import arguments into functions. [mozilla developer network]

Note the difference between parameters and arguments:

    Function parameters are the names listed in the function's definition.
    Function arguments are the real values passed to the function.
    Parameters are initialized to the values of the arguments supplied.