What is the main use of the 'return' statement in a function?

The main use of the 'return' statement in a function is to pass a value back to the caller. When a function completes its task, it often needs to send a result back to the part of the program that invoked it. The 'return' statement specifies what value should be returned. This allows the caller to receive and utilize the output of the function, which can then be used for further calculations or operations.

For example, if a function performs a calculation, using 'return' enables it to send the computed value back, making it possible for that value to be stored in a variable or processed further. This process is integral to function design in programming, as it facilitates communication between different parts of code and helps in building modular and reusable code.