CPU Cache

A CPU cache is a cache used by the central processing unit of a computer to reduce the average time to access memory. The cache is a smaller, faster memory which stores copies of the data from the most frequently used main memory locations. As long as most memory accesses are cached memory locations, the average latency of memory accesses will be closer to the cache latency than to the latency of main memory.

Read more about CPU Cache:  Overview, Cache Entry Structure, Associativity, Cache Miss, Address Translation, Cache Hierarchy in A Modern Processor, Implementation