Simple can mean something that is only made up of a few parts. It lacks complexity.
Simple can mean that something or someone is humble (lowly) or common:
- He lives very simply. "Simple living" is a way of life. It uses the ideas of Henry David Thoreau or Epicurius or Diogenes as its moral goals. Simple living says that a person needs only few and basic things to be happy.
Simplicity Facts for Kids. Kiddle Encyclopedia.