Cache
Modern software usually requires a large amount of memory in a computer in order to operate.

 

Most computers use a part of the hard disk as extra memory. Data stored in memory which is not actually needed immediately is temporarily moved into the disk cache and moved back into memory when it is needed.

The computer will seem to have more memory than it really has.

Access from disk is much slower than from RAM so the speed of operation will be reduced if disk cache is used.
Exercise : Cache
Disk cache is an area of disk which is used as extra 

The speed of operation of the computer will be slightly  when disk cache is used.

 

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