1. A book of instructions and specifications of a piece of equipment or system. User Manual, Owner's Manual, Operator's Manual, Installation Manual.
RTFM:
Read
The <
Friendly>
Manual.
2. A human operated, as opposed to automatic, action. Some lighting consoles allow both manual and timed fades. Any non-programmed action.
3. In the olden days (1960s-'70s),
dimmer, resistance and
dimmer, autotransformer systems were called manual; those newfangled
SCR dimmer systems were called remote or
preset systems.