Be able to describe your business as shortly and understandable as possible.
Venture Hacks have posted a whole entry on the idea of:
Summarize the company’s business on the back of a business card.
calling it the high concept pitch.
The definition given by Venture Hacks is:
A high concept pitch distills a startup’s vision into a single sentence.
The post also talks about how to create your high concept pitch and what benefits you are driving from having one.