Hi,
Please have a look at the circuit at:
http://www.glacialwanderer.com/_blog.../hb_relay5.jpg.
It is from the article at http://www.glacialwanderer.com/hobbyrobotics/?p=9.

The circuit it to turn on or off a AC bulb by a microcontroller. My
question is, can we somehow safely add a manual override switch near
the bulb, so that even if the microprocessor is not working, we can
turn the switch on/off manually? If yes, how will the circuit then
look like?
Sorry if this is a simple question as I am just starting in
electronics and electrical circuits.