Explain PROM, E-PROM, Cache Memory And Virtual Memory?

The PROM (Programmable Read Only Memory) can only be written to once and then cannot be changed even if power is removed. Like a CD-R.

The EPROM (Erasable Programmable Read Only Memory) can be written to and rewritten to as needed even if power is removed. Like a CD-RW.

Cache memory is volatile memory and doesn't store anything past a power loss.

Virtual memory is not really memory but temporary storage on the hard drive is an area of the drive the OS designates as temporary memory for programs that are running in the back ground and not actively being used.

PROM is Programmable Read Only Memory.it is a special chip that is a Programmable ROM as stated 1st. It is used for instance to run the program to start your computer.
E-PROM: Erasable-Programmable Read Only Memory. It is the same except it can be erased.
Cache Memory : Is VERY fast memory! It is  used either on the motherboard, (mainboard) as direct assess memory. Or in the CPU itself. Either way, it is very fast and enables your computer to access it instead of going to the Hard Drive to get info you just had in the computer.
Virtual memory is not really memory at all! It is data stored on your hard drive, since you were low on RAM memory. Windows will "Buffer" it to the hard drive. This will allow your computer to keep working instead of crashing, but it is slower, much slower! I hope that helps you.

Take care..........Big_Jack 07