Parallel processing is a method used in computer systems to simultaneously execute multiple tasks or instructions at the same time. This approach involves breaking down a task into smaller sub-tasks and distributing them across multiple processors or cores, allowing for faster and more efficient processing of data. Parallel processing is commonly used in high-performance computing and large-scale data processing applications to improve speed, performance, and scalability. It can be implemented in various ways, such as shared-memory systems, distributed systems, or hybrid systems combining both approaches. Overall, parallel processing plays a crucial role in enabling complex computations and processing tasks to be completed more quickly and effectively.