Abstract: Cloud computing refers to the various remote systems interconnected through the internet. We can outsource data, software, infrastructure from the cloud environments. Once we outsource storage there is a possibility for the data for the data to get corrupted or be hacked. The general solution is to stripe the data across multiple servers. In the setting the repair traffic will be high and the fault tolerance will be low. In order to improve the storage efficiency and the repair traffic regenerating codes have been use. In this paper we will discuss about the various regenerating codes that have evolved from time to time.