What is the term for the use of secondary memory as if it were primary memory?

What is the term for the use of secondary memory as if it were primary memory?

• A. Virtual memory
• B. Cache memory
• C. RAM
• D. Primary memory

Answer: (A)

Using secondary memory as if it were primary memory is virtual memory. It lets the system pretend there is more RAM by keeping less-used data on a hard drive or SSD and loading needed chunks into RAM on demand. The operating system and CPU work with virtual addresses and use a page table to map these to actual RAM locations. When a program tries to access data not currently in memory, a page fault triggers loading the required page from disk, and sometimes writing out another page to free space. This approach increases the apparent memory available and provides isolation between processes, though access can be slower due to disk latency. Cache memory is different: it’s a small, fast storage layer inside or very close to the CPU to speed up repeated RAM accesses, not a disk-based extension. RAM and primary memory refer to the actual main memory, not the technique of using secondary storage as an extension.

Using secondary memory as if it were primary memory is virtual memory. It lets the system pretend there is more RAM by keeping less-used data on a hard drive or SSD and loading needed chunks into RAM on demand. The operating system and CPU work with virtual addresses and use a page table to map these to actual RAM locations. When a program tries to access data not currently in memory, a page fault triggers loading the required page from disk, and sometimes writing out another page to free space. This approach increases the apparent memory available and provides isolation between processes, though access can be slower due to disk latency. Cache memory is different: it’s a small, fast storage layer inside or very close to the CPU to speed up repeated RAM accesses, not a disk-based extension. RAM and primary memory refer to the actual main memory, not the technique of using secondary storage as an extension.