This article focus on DNA Replication, which is the process whereby an entire double-stranded DNA is copied to produce a second, identical DNA double helix. It is the biological process of producing two identical replicas of DNA from one original DNA molecule. It is an intricate process requiring the concerted action of many different proteins. DNA replication, like all biological polymerization processes, proceeds in three enzymatically catalyzed and coordinated steps: initiation, elongation and termination.