A queue is a data structure or system used to manage and organize items or tasks in a specific order, typically following the "first-in, first-out" (FIFO) principle. This means that the first item added to the queue will be the first one to be processed or removed. Queues are commonly used in computing for managing tasks, handling requests, or controlling the flow of data, such as in print spooling, customer service systems, and network traffic management.