Personally I'm not entirely sure how much technical detail you require, only in a generally digestible fashion. However, given that I have recently read answers provided to numerous questions regarding black holes*, formulated for the 'general reader' but by someone who, to drastically understate, certainly knows much, much more than myself, I'll quote:
A black hole is an incredibly dense
celestial object containing so much
mass it has generated a powerful
gravitational field from which not
even light can escape. Anything that
falls into a black hole will be
crushed out of existence.
Black holes are spherical and expected
to be spinning, dragging the spacetime
continuum like honey around a spinning
spoon. In these confused regions of
spacetime, it won't be clear whether
you're travelling through time or
space or both.
Just like any object that hits the
black hole, light too will be
swallowed completely and quite
possibly forever. Light that misses
the black hole, but passes very close
to it will be deflected onto a new
course through space.
Nothing, not even information is
expected to be able to escape from a
black hole. This s contentious because
if, as Stephen Hawking suggests, black
holes eventually evaporate and die,
they must be radiating particles. In
turn, it should be possible to detect
and measure these particles, but
currently none of our telescopes are
able to get any readings when pointed
at a black hole - these areas are void
of any information. So, to resolve
this contradiction , it's suggested
even information is sucked into the
heart of the black hole.
We don't know what happens at the
centre of a black hole. Our current
theories break down because they can't
deal with infinitely dense objects.
So, physicists are trying to develop
new theories of gravity to answer what
lies at the bottom and whether they
lead anywhere. Called a singularity,
one is thought to exist at the centre
of every black hole.
This may be far less technical than you desire - let us know if so. Though, even so it is an easy read with enough of an idea and general knowledge to be contributed, I believe.
*Source: BBC Focus, Brian Cox, April 2011