To return to a previous state by
undoing the effects of one or more
commands. The undo command is a valuable
feature supported by many
software products. It lets you try unknown commands with less risk, because you can always return to the previous state. Also, if you accidentally press the wrong
function key, you can undo your mistake.
Many programs allow you to undo an unlimited number of commands. Each time you press the undo key, the previous command is undone. You can roll back an entire editing session this way. Other programs impose a limit on the number of commands you can undo.
