ii. Memory Management-

           Memory management refers to management of Primary Memory or Main Memory. Main memory is a large array of words or bytes where each word or byte has its own address.

        Main memory provides a fast storage that can be accessed directly by the CPU. For a program to be executed, it must in the main memory. An Operating System does the following activities for memory management −

a. Keeps tracks of primary memory, i.e., what part of it are in use by whom, what part are not in use.

b. In multiprogramming, the OS decides which process will get memory when and how much.

c. Allocates the memory when a process requests it to do so.

d. De-allocates the memory when a process no longer needs it or has been terminated.