Recursion is a process in which a function calls itself directly or indirectly. It is a widely used phenomenon in computer science used to solve complex problems by breaking them down into simpler ones. Recursion occurs when the definition of a concept or process depends on a simpler version of itself. It is a powerful tool in writing algorithms and comes directly from Mathematics, where there are many examples of expressions written in terms of themselves.
In a recursive function, the solution to the base case is provided, and the solution of the bigger problem is expressed in terms of smaller problems. A recursive function definition has one or more base cases, meaning input(s) for which the function produces a result trivially (without recurring), and one or more recursive cases, meaning input(s) for which the program recurs (calls itself) ). It is essential to know that we should provide a certain case to terminate this recursion process.
Recursion can be inefficient and lead to stack overflows if not used carefully. Each function call adds a new frame to the call stack, which can cause the stack to grow too large if the recursion is too deep. In addition, recursion can make the code more difficult to understand and debug, since it involves a function calling itself.
