When we use recursion to solve a problem, we have:
1. a problem that contains one or more problems that are similar to itself
2. a version of the problem that is simple enough to be solved by itself, without recursion, and
3. a way of making the the problem simpler so that it is closer to (and ultimately the same as) the version in 2.

What is 2 called?

• The simple case
• The inductive case
• The iterative case