abstract:The Alt key (pronounced ) on a computer keyboard is used to change (alternate) the function of other pressed keys. Thus, the Alt key is a modifier key, used in a similar fashion to the Shift key.
It works like this: After downloading a tiny bit of software, users mouse over any word on any Web page, within any e-mail, within any document, hit the "Alt" key and automatically get an Answers.com page with information described above.
But you can also remap other key functions such as Ctrl, Shift, Alt, various click and scroll mouse functions, and also launch other game profiles and third party programs.