How does cache memory speed up a computer's processing?

Cache memory accelerates a computer's processing by acting as a high-speed, supplementary storage layer that sits between the central processing unit (CPU) and the main memory.12

It improves performance through the following mechanisms:

• Reduced Latency: Cache is built using static RAM (SRAM), which is significantly faster than the dynamic RAM (DRAM) used for main memory because it does not require periodic refreshing to retain data.3
• Proximity and Efficiency: By storing only the most frequently accessed instructions and data, the cache allows the CPU to retrieve necessary information much faster than it could from the larger, slower main memory.13
• Streamlined Access: When the CPU needs data, it checks the cache first. If the information is present, the CPU avoids the delay of accessing the main memory, thereby reducing processing bottlenecks and keeping applications responsive.13

Because cache is expensive and requires more physical space per bit than DRAM, it is used in limited quantities to provide the most critical data exactly when the processor needs it.3