Define virtual memory

Define virtual memory
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Virtual memory is a memory management capability of an operating system (OS) that uses hardware and software to allow a computer to compensate for physical memory shortages by temporarily transferring data from random access memory (RAM) to disk storage. OR Virtual memory is the separation of user logical memory from physical memory. This separation allows an extremely large virtual memory to be provided for programmers when only a smaller physical memory is available. Virtual memory makes the task of programming much easier, because the programmer no longer needs to worry about the amount of physical memory available, or about what code can be placed in overlays, but can concentrate instead on the problem to be programmed. 
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What is Virtual Memory?

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.................. is a facility that allows programmers to address memory from a logical point of view, without regard to the main memory, physically available. A) Visual memory B) Real memory C) Virtual memory D) Secondary memory

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