queues.js

// Create an empty queue.
var queue = [];
// Add values to the end of the queue.
queue.push(1);                      // queue is now [1]
queue.push(2);                      // queue is now [1, 2]
// Remove the value at the top of the queue.
var topOfQueueValue = queue.shift(); 
console.log(topOfQueueValue)        // returns 1 
// The queue now has just one element in it.
console.log(queue)                  // returns [2]