Diversity in Roles

novices walk up and use systems

interface affords restricted set of tasks

tutorials for complex uses

casual standard idioms

recognition over recall

reference guides

interface afforts basic task structure

intermediate advanced idioms

complex controls

reminders and tips

interface affords advanced tasks

expert shortcuts for power use

interface affords full task +

customization

kiosk

WWW

most shrink-

wrapped

software

custom

software