What is recursion in programming?

Recursion in programming refers to the concept where a function calls itself in order to solve a problem. This technique is particularly useful for breaking down complex problems into simpler sub-problems that are easier to solve. By defining a base case that stops the recursion, along with a recursive case that brings it closer to the base case with each call, developers can create elegant solutions for problems such as navigating trees, calculating factorials, and generating sequences like Fibonacci numbers.

This form of function definition allows for clean and concise code, which can be easier to read and maintain compared to iterative approaches. Recursion effectively utilizes the call stack to keep track of multiple function calls, each with its own local variables and parameters, thus enabling a straightforward implementation of algorithms that exhibit recursive structure. For example, in searching or traversing data structures like trees, recursion simplifies code and avoids the need for explicit data management that iterative solutions would require.

While the other choices discuss important concepts in programming, they do not accurately describe what recursion fundamentally is.