An L2 cache, or Level 2 cache, is a type of memory used in computers to store frequently accessed data and instructions. It acts as a bridge between the main memory (RAM) and the CPU, helping to speed up data retrieval. By keeping important information closer to the processor, L2 caches reduce the time it takes for the CPU to access data, improving overall system performance. Typically larger than the L1 cache but slower, L2 caches can be found on the CPU chip or nearby. They play a crucial role in enhancing the efficiency of the CPU, allowing it to process tasks more quickly. This is especially important in modern computing, where speed and efficiency are vital for applications and games.