Index[SYMBOL] [A] [B] [C] [D] [E] [F] [G] [H] [I] [J] [K] [L] [M] [N] [O] [P] [Q] [R] [S] [T] [U] [V] [W] [X] [Y] unittest.js test suites updating versus replacing usability affordances Ajax, when to use blank slates capabilities detection coach content consistent page elements cross-platform development direct manipulation grips help nuggets idempotence key commands and mentor metaphor mind hacks and personal assistant metaphor platforms, differing principles of program model Rails and responsiveness, increasing tagging tour guide metaphor trainer metaphor user model Web HTTP page Windows versus Mac program models |