Refactoring for designers

Ryan Singer at 37signals explains code refactoring to designers so that they can use it correctly in a design context.

Designers sometimes use the word “refactor” in a loose way. I think they overhear the word from programmers without getting the precise meaning. This article will introduce the term to designers so they can gain the same advantages that programmers have from a clear understanding.
How do designers loosely understand refactoring? Many take it to mean “rearranging” a design or “adjusting without completely rethinking” it. Refactoring actually means something else. It means changing the way a design is built without changing the way it looks from the outside.