Queue
Pronounced "Q," a queue is a temporary location that stores requests unable to be fulfilled immediately. For example, a printer may receive multiple requests from different programs and users simultaneously or in quick succession. Because a printer only produces one page at a time, the rest of the jobs are queued; software manages the additional incoming requests while the printer is busy.
With most software and hardware that utilize queues, the items are processed as FIFO (first in, first out). In other words, the first request that gets placed in the queue is the first to get processed.
It's common for people to confuse "que" for "queue." If you're discussing a line or waiting of any sort, you would use the spelling "queue."
Where a queue is encountered
A queue is encountered anywhere waiting is involved, and there are not enough devices or people to provide a requested service. Below are examples of where you're most likely to encounter a queue.
- Customer service or a help desk - When needing help, you may have to wait in a queue on the phone, chat, or e-mail.
- Networking - If a network is busy with other users, packet queuing is used to help break up traffic. See our page on packet switching for further information and examples.
- Printer or other peripheral - If you need to use a device that is currently servicing more than one user, you may be placed in a queue.
- In an online game, "queuing up" is joining a wait list to enter a match or game with other players. In a competitive environment, these queues may attempt to match players at a similar skill level.
- With music, you may add songs to a queue. Unless otherwise specified, they play in the order they were added.
What is a queuing system?
A queuing system is software responsible for managing the overall queue, which involves the following.
- Accept or deny the input sent to the queue.
- Place any accepted input in the queue.
- Order the queue as required (e.g., FIFO or LIFO (last in, first out)).
- If part of a queuing network where a queue shares its data with other queues, share queue data with other queues as changes happen.
- If another queue has affected any of the data in the queue, re-order the queue.
- Output and remove queue items when ready to be processed.
Examples of queue management providers
Below are some companies that provide other companies with a queue management system.
Business terms, FIFO, Line, Order, Priority queue, Q, Spool, Wait