Define Function Prototype

Question

explain briefly

Answer 1

A function prototype is the same as a function declaration. It looks like the actual function definition without the function body (and the parameter names can be missing).
Function definition with function body:
int add(int a, int b) {
// function body
return a+b;
}
Function declaration / protoype:
int add(int, int);

Answer 2

Like the header of a function giving it's name and types of input and output data.