The basic task of a system that manages the memory is management of an order memory of a RAM and secondary memory devices. It is the one of the most important parts of the operating system. Memory management is involved as a resource to be shared and assigned to among a number of active processes in treating the main memory. There is always this demand to have more memory than the physical memory. The memory management allows these things to be done with the help of a virtual memory concept where the virtual memory can be many times larger as compared to the physical memory. There is a need for a requirement to be satisfied when managing a memory and these requirements will help efficiently manage the memory and these are relocation, protection, sharing, logical organization and physical organization.