SRAM - Static Random-Access Memory
Static RAM is a type of RAM that is much faster than the typical "dynamic" RAM (DRAM). The name "static" is given to it because of the fact that the memory needs not to be refreshed frequently, like in other type of RAMs namely the Dynamic RAM. SRAM is much more expensive than DRAM - the very reason for its use only in memory cache.
As compared to DRAM which gives an access times of about 60 nanoseconds, SRAM supports an access time of 10 nanoseconds. This results in reduced "cycle time".
In contrast to DRAM, SRAM uses a form of flip-flop that holds each bit of memory. This static memory cell takes lot more space on a chip than a typical dynamic memory cell. As a result, you get less memory per chip as compared to its dynamic counterpart.