80 / 20 Rule

Focus on the critical 20% of a system that provides 80% of its functionality.

Accessibility

A system must be useable by people with a range of abilities / knowledge. Accessibility can be broken down into: perceptibility, operability, simplicity, and forgiveness.

Advance Organizer

Present brief chunks of information before presenting all new information. Two flavors: expository (audience has little to no knowledge on subject) and comparative (audience has existing similar knowledge.)