Parameters & Return Values

Parameters and return values are the primary mechanisms for communication between functions in C. They allow functions to be flexible and reusable by enabling them to operate on different data and produce results that can be used elsewhere in the program. **Parameters**, also known as arguments, are variables listed in the function's declaration and definition that act as placeholders for the data the function will receive when it is called. When you call a function, you pass values (or variables) to it, and these values are copied into the function's parameters. This mechanism in C is known as **pass-by-value**. This means the function works with a local copy of the data, and any changes made to the parameter inside the function do not affect the original variable in the calling function. This is a safe way to pass data, as it prevents accidental modification of variables. A **return value** is the data that a function sends back to the part of the program that called it. The `return` statement is used to specify this value. The data type of the value being returned must match the return type specified in the function's declaration. A function can only return a single value. If a function does not need to return any value, its return type should be declared as `void`. Functions with a `void` return type can still use the `return;` statement without a value to exit the function prematurely. By using parameters to provide input and return values to provide output, you can create self-contained, modular functions that are easy to integrate into any part of your code.