Recursion and iteration who is better

Question

Considering the speed, number of steps and the complexity which system or writing code is ideal or usually suitable in most cases

Answer 1

if you can avoid recursion - do, however as @merkafter said, trees and graphs are mostly handled by recursion and there is no escaping that.
One tip - the moment you start writing a recursion, write your exit condition, then do everything else.

Answer 2

Iteration-based solutions are always faster but there are problems which are much easier to solve with recursion.

Answer 3

It depends on the problem.
To calculate the fibonacci numbers for example an iterative technique is better while recursion if often better in terms of graphs and trees.