How the keyboard can be used for commands, from its reserved keys, to key equivalents, interface controls, and keyboard actions.
keystroke
A friend suspects their partner might be snooping on their Mac. How can they check?
I seem to have inadvertently hit a combination of keys that has disabled the upper case letter V on my keyboard. How can I reset that?
This second article considers how text is entered into your Mac: mainly by the keyboard, but also briefly covers speech and scanned input.
The Eclectic Light Company 