A family of Microsoft spreadsheet software with tools for analyzing, charting, and communicating data.
Your computer likely has alternate functions assigned to each the the F1-F12 keys. There could be an F-Mode or F-Lock key or a Fn+<some key> keystroke combination to toggle between the F1-F12 and alternate modes of operation. If you cannot find the method of toggling between the two modes, post back with the make and model of your computer/laptop/notebook and someone might be able to offer you the correct method.
One example: