Answer:
In his book, 'The Black Hole War' Leonard Susskind came up with a good visual example of a Black Hole. Constantly fill a bath tub with water while the plug is pulled out. The vortex in the water is as a black hole. If you could imagine bathtubs in every other dimension emptying out at the same plug hole you have created a black hole. He then adds fish. Read the book ... it's great, even if coming to the wrong conclusion at the end due to personal 'belief based' reasons.