What are the differences between sram and sd ram?

SRAM (Static Random Access Memory) is faster and more expensive than SDRAM (Synchronous Dynamic Random Access Memory). SRAM retains data bits as long as power is supplied, making it ideal for cache memory in CPUs, while SDRAM must be refreshed periodically to maintain data, which can slow down performance. Additionally, SRAM uses more transistors per memory cell compared to SDRAM, resulting in lower density and higher cost for SRAM. SDRAM is typically used for main system memory in computers due to its cost-effectiveness and sufficient speed for most applications.