What is Cache Memory ?

CACHE Memory is a very high spead and comparably expensive type of memory. It is used to speed up the performance of processors by allowing it them to use it as a "workspace" for comparably small amounts of information that must be worked uppon, stored, recalled, restored, etc, very frequently during some operations. If all this would have been done on external normal memory, your computer would be much - much slower.Now ask, why isn't all memory like CACHE memory?Well, because of the technology used, CACHE memory is bit-by-bit more expensive than - say - SDRAM or DDR memory. It would make PC prices skyrocket. What we usually have is maybe 500K up to 2 MB (even higher) of CACHE Memory and it usually comes inside the processor.Try it out -- check out prices of different pentium processors, where the only changes are in CACHE memory. Prices will vary significantly.