paramters in c language

parameters are the communication between the calling and called function .
Arguments and parameters refer to the variables or expressions passed from the caller of a function into the function (or macro).

there are two types of parameters
1. actual parameter
2. formal parameter

Distinguish between actual and formal parameters?

Actual parameters	Formal parameters
1.       The parameters specified in the function call are called as actual parameters	The parameters specified in the function declaration are called formal parameters
2.       Sending the value or variable or expression from   the function call	Receiving the value or variable from the actual parameters
3.       Ex: swap(a,b); or swap(2,3); Here a,b or 2,3 are actual parameters	Ex: void swap(int a, int b)       {       } Here a,b are formal parameters
4.       Passing the parameters a,b to swap()	Here a,b are receiving the value or variables
5.       Actual parameters may be variable,value or expression, or structure,address	It must be variable or structure or array but not values or expressions

argument: that which is passed into a function by its caller (or macro by its invoker)
parameter: that which is received by the function or macro

Functions