Recursion

Recursion is when a function calls itself. This technique is elegant for problems that can be broken into smaller versions of the same problem. While it might seem strange at first, recursion is a natural fit for many algorithms. Data engineers encounter recursion when traversing nested JSON, processing tree structures, working with file system hierarchies, or implementing divide-and-conquer algorithms. It's also a favorite topic in technical interviews. The Two Parts of Recursion Every recursive function must have two parts: a base case that stops the recursion, and a recursive case that calls itself with a smaller problem. Each call to countdown passes a smaller number. Eventually n reaches 0, hitting the base case and stopping. Without the base case, the function would call itself forev