What is recursion and what are its essential components?

Recursion is a technique where a function calls itself to solve smaller subproblems of the same type. Essential components are: Base case (termination condition that stops recursion), Recursive case (function calls itself with modified parameters moving toward base case). Each recursive call adds to the call stack. Common uses include tree traversal, divide-and-conquer algorithms, and mathematical computations like factorial and Fibonacci.