L1 cache is a small, high-speed memory located inside the CPU (Central Processing Unit). It stores frequently accessed data and instructions, allowing the processor to retrieve them quickly without needing to access slower RAM (Random Access Memory). This helps improve overall system performance by reducing latency. Typically, L1 cache is divided into two parts: one for data and another for instructions. Its size is usually limited, often ranging from 16KB to 64KB, but its speed is crucial for efficient processing. By keeping essential information close to the CPU, it enhances the speed of computing tasks.