Earlier, we saw how we can simply swap out a simple queue for a priority queue and not worry about the functional change that it might cause; similarly, we can swap out priority queues for a higher-performant variant of them: circular dequeues.
Before we start working on a comparison, we will need to discuss circular queues and why we need them.
The difference between a circular queue and a simple queue is that the back of the queue is followed by the front of the queue. That being said, they are not functionally different. They still perform the same operations, and produce the same results; you might be wondering where exactly they differ and what's the point if the end result is the same.