All about Blackholes

An object that sits in space minding its own business. A black hole is an object inspace from which the escape velocity is equal to the speed of light. Since the speed of light is the fastest we know, it also means that nothing can travel fast enough to excape from inside a black hole. Simple as that. What is escape velocity??? Every object in space has an escape velocity. It is the velocity you will need to get out of its gravitational influenze. A simple formulae is

Escape Velocity = (2GM/R)1/2

were, G= Gravitaional Force, M is the mass of the body, and R is the radius of the body....why not try working
the escape velocity of the earth, then?