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
'If one wishes to obtain a definite answer from Nature one must attack the question from a more general and less selfish point of view.'