Dumb, really dumb, newbie question

["Brian E. Seppanen" <seppanen@pconline.com>]

I've seen it mentioned a thousand times, but have no clues as to what it
refers to. Lucky? maybe.
What is a "Segmentation Fault?"  What specifically are the
manifestations?  Dumping a core file?  A big nasty error message on the
command line stating segmentation fault?   Would it be obvious if it
occurred?  I've had problems with a couple of different programs which I
can't quite figure out, and I've noticed with these programs many users
are complaining of Segmentation faults, and I'm wondering if I might be
having the same problem.
Thanks for the insight.

Brian Seppanen
seppanen@pconline.com