You know the row of mysterious F's numbered 1 through 12 at the top of your keyboard. These are the function keys, or as some engineers call them, "the guardian angels of the keyboard." If this is your first time noticing our functional friends, you're not alone! In common usage the word function refers to the purpose for which something is designed. On the keyboard, however, the function keys can accomplish anything from summoning help (F1) to accessing hidden recovery gateways (F11).