Recursion and the Call Stack
A recursive function is just a function that calls itself, and the machine does not care — each call pushes another frame onto the stack. This video shows those frames as they are pushed and popped, and what that means for memory, depth limits, and performance.
Topics covered:
- Stack frames: what the machine pushes on every call
- The base case as the only path that unwinds the stack
- Tail calls and why some languages optimize them away
- Stack overflow: how deep is too deep, and why
- Converting recursion to an explicit stack or a loop
- Memoized recursion: where the repeated work actually was
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