Tolerance is the capacity of software to forgive user
errors, such as when they accidentally click on a link or make other typical
errors. A tolerant interface will allow the user to cancel, go back, or undo an
action.
Robustness is the capacity of a system to cope
with stressful or unusual runtime environmental problems, such as
running low on memory or disk space, equipment faults (e.g. printer not found),
dumb/invalid/unexpected user inputs, high usage levels, and uncommon but
feasible events that would break lesser software - for example, coping with a
user whose street address is just "11 Broadway" with no
"Rd", "St" or "Av" field.
