Subprogram

A subprogram is a named sequence of statements that performs a specific task. It is a fundamental concept in computer programming, enabling the modularization of code and promoting reusability. Subprograms are also known by various other terms depending on the programming language, such as functions, procedures, methods, routines, or subroutines.

The primary purpose of a subprogram is to break down a complex problem into smaller, manageable units. Each subprogram is designed to accomplish a well-defined objective. This modular approach makes programs easier to understand, debug, and maintain. Developers can write a subprogram once and call it multiple times from different parts of the program, avoiding redundant code.

Subprograms can accept input values, known as arguments or parameters, which they use to perform their operations. They can also produce output values, often referred to as return values, which are passed back to the calling code. The interface of a subprogram, including its name, parameters, and return type, defines how it interacts with other parts of the program.

The concept of subprograms is supported by most programming languages, although the specific syntax and features may differ. For instance, some languages distinguish between functions that always return a value and procedures that do not. The use of subprograms is a cornerstone of structured and object-oriented programming paradigms.