Parallel execution refers to the simultaneous processing of multiple tasks or operations. This approach is commonly used in computing to improve efficiency and speed, allowing programs to run faster by dividing workloads across multiple processors or cores. By executing tasks in parallel, systems can handle larger datasets and complex calculations more effectively. In the context of databases, parallel execution can enhance query performance by distributing the workload among several threads or processes. This technique is particularly beneficial for large-scale data processing, where tasks like sorting or aggregating data can be completed more quickly, ultimately leading to better resource utilization and reduced response times.