Which type of memory is primarily used as cache memory?

SRAM, or Static Random-Access Memory, is primarily used as cache memory due to its speed and efficiency. It is designed to be faster than other types of memory, particularly Dynamic Random-Access Memory (DRAM), which is used for main memory but is slower in operation.

The functionality of SRAM comes from the way it stores data. Unlike DRAM, which needs to be refreshed thousands of times per second to maintain data integrity, SRAM retains data as long as power is supplied without the need for refreshing. This characteristic allows SRAM to offer quicker access times, making it ideal for caching purposes where speed is essential.

Furthermore, cache memory, which acts as a buffer between the CPU and main memory, requires a type of memory that can operate at high speeds to ensure that the processor has immediate access to frequently used data. The speed of SRAM allows CPUs to access data more rapidly, thus enhancing overall system performance.

Other types of memory, such as EEPROM and NVM, serve different purposes and are not as suitable for cache applications due to their slower access speeds and complexity in operation compared to SRAM.