A Queue is a data structure or system in which elements are added to the back (enqueue) and removed from the front (dequeue) in a first-in, first-out (FIFO) order. Queues are commonly used in programming and computing to manage tasks, process requests, and handle data in a controlled and orderly manner. For example, in operating systems, queues are used to manage processes waiting for CPU time, ensuring that each process is handled in the order it was received. In networking, queues manage packets waiting to be transmitted over a network, maintaining the sequence and order of data delivery.

Queues are also widely used in messaging systems, such as message queues, where they enable asynchronous communication between different parts of an application or between different applications. By using a queue, tasks or messages can be stored and processed sequentially, ensuring that no data is lost or processed out of order. Queues are an essential component in many algorithms and systems, providing a simple yet effective way to manage and process data efficiently, especially in scenarios involving concurrency, parallel processing, or resource management.