What is an argument? Differentiate between formal arguments and actual arguments in C?

Answer 1

1) Arguments of the function are the parameter which are passed from the caller to the called function or from the command line to the main function.

2) The arguments passed to the functions while the function is called is known as the actual arguments, whereas the arguments declared in the function header is called as formal arguments.

Answer 2

The arguments passed to the functions are called actual arguments.
The arguments declared in the function definition is called as formal arguments.

int addition(int a, int b) /* a and b are formal arguments*/ 
{
  ...
} 

void main() 
{ 
  int i
  .... 
  i = addition(1,2); /* 1 and 2 are called actual arguments*/ 
  ... 
}