Oldsmobile wont start.

A neighbor across the street from me owns a 1995 Oldsmobile, 3900 Series
II engine.This morning, his car wont start.He said the battery is good
and the battery cables are clean and tight.The horn works and the little
warning beeper works.When he switches on the ignition, there is nothing
at all from the starter motor.What would likely be the reason his car
wont crank?
cuhulin