Dark energy of the universe

It has been conclusively proved, from various observations and specifically by studying type 1a supernovae, that we live in an accelerating Universe. All the galaxies are receding from one another, not with the deceleration predicted by General Theory of Relativity as per Einstein's original formulation, but with acceleration. Dark Energy is the presumed source of this acceleration and is known at present to constitute nearly 73% of the energy budget of the Universe. An introductory and semi-popular account will be given of the discovery, present status and implication of this entire phenomenon. (author)