Compaq 1600 Series - Manual (Page 29)

Mobile Internet PC Features 3-7
Using the Function Keys
Use the function keys on the keyboard to perform repeated tasks quickly. The
function keys are located on the top row of the keyboard. The Fn key activates a
function key. It is located in the lower-left area of the keyboard.
To use a function key, press the Fn key at the same time you press a function key.
Function Keys and Fn Key