It is believed that the matter and radiation in the Universe were formed some fifteen billion years ago after a huge bang, called Big Bang. A fireball was created in this big bang. Now challenge is that how the fireball changed to the Universe we live in today. As laws of physics are improving day by day, we are becoming able to look further back in time, and to get knowledge about the evolution of this Universe. It is believed that matter and antimatter created in the big-bang were in equal amounts and also it is said that most of the antimatter was annihilated on matter during the formation of the Universe. This antimatter annihilation started when most of the matter we see in the Universe today was already in the form of hadrons made of quarks. But before this hadronized Universe, it had passed through a phase of quarks and gluons in free states. Physics of Quark Gluon Plasma QGP is the field in which physicists are trying to recreate this phase, and to study it in the laboratory.