Command representation (3)
Function keys and hot keys general - if function keys or hot keys are used for command input, their use should be obvious to users or the key assignments should be readily accessible and these assignments should be consistent throughout the application. [NOTE consider using function keys and hot keys for frequently used commands or when it is important to speed up command entry] function key consistency - function key assignments for commands should be consistent across related tasks within an application, particularly for ‘generic’ commands like help. hot key consistency - hot keys should have the same meaning throughout the whole application. [NOTE if commands can be accessed by menu as well as typing, the hot key assignments should be the same as the accelerators used in the menus] [EXAMPLE ALT/c is used for cancel and it is used consistently to provide that action throughout the application] consistent grouping of modifiers - if modifier keys (e.g. CRTL or ALT keys) are used with other keys, there should be a consistent rule of the modifier key usage. [EXAMPLE ALT + letter keys is used for navigation and window manipulation and CRTL + other letter keys is used for data manipulation] limited modifiers - multiple simultaneous modifier keys should be used in hot keys only if there are more commands than can be accommodated meaningfully by single modifier keys. [EXAMPLE in a dialogue, ALT+p (rather than ALT+CRTL+p) is used to issue a print command] [NOTE if possible, use letter keys that are mnemonic in combination with modifiers; it may be desirable to require the depression of more than one modifier key to reduce the possibility of accidentally causing a destructive action]