This structure retrieves elements in the opposite order from that of a stack.
An automaton named for one of these structures with an infinite amount of memory is equivalent to a Turing machine. If this data structure has a limited size, it can be implemented to operate in constant time using a circular buffer. This structure is used to store the elements to be visited in a breadth-first search. One type of this data structure is often implemented with a heap, and retrieves elements of highest priority first. That is its "priority" type. This structure retrieves elements in the opposite order from that of a stack. For 10 points, name this first-in, first-out data structure, which can be used to model a checkout line.
An automaton named for one of these structures with an infinite amount of memory is equivalent to a Turing machine.
queue [or priority queue before "priority"]