E stands for the energy of the object in question. m stands for it's mass, and c stands for the speed of light in vacuum, ( which is: c = 2.99792458 108 m/s )
Answered by: Anton Skorucak, M.S. Physics, PhysLink.com Creator
'To myself I seem to have been only like a boy playing on the seashore, and diverting myself in now and then finding a smoother pebble or a prettier shell than ordinary, whilst the great ocean of truth lay all undiscovered before me.'