What is a function?

A function is fundamentally a sequence of instructions that performs a specific task. In programming, it acts as a reusable block of code designed to carry out a defined operation or set of operations. Functions help to break down complex problems into simpler, more manageable pieces, promoting modularity and code reusability. By defining a function, you can execute the same logic multiple times throughout a program without needing to rewrite the code, which not only saves time but also reduces the potential for errors.

The primary purpose of a function is to encapsulate behaviors that can be invoked when needed, often with inputs (known as parameters) and returning outputs (known as return values). This encapsulation allows developers to maintain clarity in their codebase, making it easier to read and maintain over time.

While other choices relate to important concepts within programming, they do not accurately define a function. A type of data structure focuses on how data is stored and organized, a way to store variables pertains to variable declaration and storage rather than functional behavior, and an error handling mechanism is about managing exceptions during execution rather than defining tasks through code.