Keys with an Fn key or F Lock provide two sets of commands for many keys. This includes the top row of standard function keys (F1–F12).
Standard commands are labeled on the front of the keys (such as F3). Alternate commands are labeled on top of the keys (such as Redo). In some programs, the function of a standard command and an alternate command may be the same (for example, F1 typically displays Help for the active window, and on some keyboards, the alternate command for F1 is also Help).
The following table specifies the default key assignments for the alternate command keys. You can reassign many of them using Microsoft Mouse and Keyboard Center.