Dell Inspiron 5400 2n1 Setup And Specifications page 23

Function key
The Fn key is also used with selected keys on the keyboard to invoke other secondary functions.
Table 24. List of keyboard shortcuts
Function key
Re-defined key (for multi-media
control)
Behavior
Pause/Break
Sleep
Toggle between power and battery-status light/hard-drive activity
light
Toggle scroll lock
System request
Open application menu
Toggle Fn-key lock
Page up
Page down
Behavior
Home
End
Keyboard shortcuts 23