What is meant by cache Memory ?

Cache memory is also called temporary memory. This kind of temporary memory is used in all forms of computing to increase the speed of processing.

Why does Cache increase the processing speed?

Say a CPU is processing information. It would be better to have the information it requires to process it with it to increase the speed of processing, than to retrieve it from the hard-disk every time it is needed as retrieving it from the hard disk take more time (This increases the time of processing).

Caching may be Memory caching or disk caching.

Memory caching is similar to the one explained earlier. It is the cache memory which resides in the CPU, which stores the information temporarily for processing. This increases the speed of processing.

In memory caching, the cache that is built into the CPU itself is called Level 1 caching. It is also called L1 caching. Some CPU’s have another chip installed near it to increase cache. This is called Level2 caching. It is also called L2 caching. Some CPU’s have this kind of chip directly built up inside them .They also have an additional chip. In this case the additional chip cache is called Level 3 caching.

In case of Disk caching Random access memory comes into account. It is used to store the temporary files, increasing the aped of their retrieval. These files mainly involve runtime files for various programs. This makes the application run faster. The more the RAM the better is the performance. However disk caching is slower when compared to memory caching. But memory caching is costlier.

In the recent features, hard-disks will be replaced completely with flash memories. Retrieving files from a flash drive is faster when compared to a drive with platters .It is even faster than the Random access Memory.