Double-ended queue

Deque Double-ended queue (inputs and outputs may be at both ends in the most general deques). 

Two kinds of simple lists are stacks and queues. A stack is a data store where both input and output occur at the same location the general name for such a place is a port. Stacks are characterized by last-in-first-out data handling. A queue is a two-port store characterized by first-in-first-out data handling. A queue is a more versatile data structure than a stack. A method for storing a queue in a fixed fast memory space uses circular wrapping of the data (modulo storage). There is another kind of linear list—a deque or double-ended queue, which has two ports. In the most general deque, input and output can take place at both ports. 

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