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.

Level 1 cache actually resides in the processor core and runs at the processor speed, very fast compared to the other RAM. Due to physical space constraints the size of this cache is small.Used for temporary storage of instructions and data organized in blocks of 32 bytes.Primary cache is the fastest form of storage. Because it’s built in to the chip with a zero wait-state (delay) interface to the processor’s execution unit, it is limited in size.

Level 2 cache rests outside the CPU core and before the DRAM. This cache will typically run at speeds below the processor speed, but it still faster then the DRAM and is far larger then L1 cache.The aim of the Level 2 cache is to supply stored information to the processor without any delay