Memory uses the hard drive to substitute for ram.

Virtual memory

Explanation:

The RAM is the main/primary memory of the computer because its data is easily accessible when needed by the computer while the hard drive/hard disk is the secondary memory/permanent memory of the system.

The Virtual memory is a memory management capability of a system that allows the transfer of data from the main memory which is the Ram to a secondary memory like the hard drive. this is mostly done when the Ram is running low on space and probably slowing the system down.

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