What function does cache memory serve in a computer system?

Cache memory plays a crucial role in computer systems by allowing the processor to access data more quickly. It functions as a high-speed storage area situated between the CPU and the main memory (RAM). When the processor needs to access data, it first checks the cache memory, which is designed to store frequently used data and instructions. Because cache memory is faster than main memory, this mechanism significantly reduces the time it takes for the CPU to retrieve information, thereby improving overall system performance.

The other options do not accurately describe the primary function of cache memory. Cache does not store permanent data, as it is volatile and loses its contents when the power is off. It also does not directly increase hard drive speed; rather, it provides quicker access to data needed for processing, independent of the slower hard drive speed. Furthermore, while cache memory can indirectly benefit video rendering by speeding up access to relevant data, it is not specifically designed for enhancing video rendering tasks. Its main purpose remains focused on optimizing CPU data retrieval speeds.