What are black holes? Do they really exist? How can we find them?

By putting a black hole into a familiar environment like a desk, one may experience what `curvature of space' means in a new way, understanding the cosmological effects of light bending and gravitational lenses from this playground.

Lecture notes for a course on Black Holes given at Cambridge. The course covers some of the developments in Black Hole physics of the 1960s and 1970s.

Loosely speaking, a black hole is a region of space that has so much mass concentrated in it that there is no way for a nearby object to escape its gravitational pull

From the University of Illinois. Educational sequence suitable for high school students.

A good list of FAQ questions with detailed answers.

Laying your hands on a black hole is hard (and dangerous) to do, but there are ways to understand these objects and avoid the pain of dimension-bending.

Provides information on black holes.