1. [n]  a braid of hair at the back of the head
2. [n]  (information processing) an ordered list of tasks to be performed or messages to be transmitted
3. [n]  a line of people or vehicles waiting for something
4. [v]  form a queue, form a line, stand in line

1. \Queue\, n. [F. See {Cue}.]
   (a) A tail-like appendage of hair; a pigtail.
   (b) A line of persons waiting anywhere.
   
   

2. \Queue\, v. t.
   To fasten, as hair, in a queue.
   
   

A first-in first-out data structure used to sequence multiple demands for a resource such as a printer, processor or communications channel. Objects are added to the tail of the queue and taken off the head.

A typical use of queues in an operating system involves a user command which places something on a queue, e.g. a file on a printer queue or a job on a job queue, and a background process or "demon" which takes things off and processes them (e.g. prints or executes them). Another common use is to pass data between an interrupt handler and a user process.