Explain the concept of virtual memory and its purpose in the operating system

Virtual memory is a mechanism of the operating system that allows programs to use more memory than is physically available in the system. The OS creates an abstraction where each process is provided with its own address space, independent of other processes and the actual amount of RAM.

Purpose of virtual memory:

• Process isolation: each process operates in its own virtual address space, which enhances security and stability.
• Efficient use of memory: rarely used data can be swapped out to disk (swap file), freeing RAM for active tasks.
• Simplification of programming: developers do not need to worry about the physical location of data.

Example: if a computer has 4 GB of RAM, and a program requires 6 GB, the OS can "swap" parts of data between RAM and disk using virtual memory, creating an illusion of larger memory capacity.