Priority Queue
In plain terms
A queue where items are served by priority, not arrival order.
Going deeper
A priority queue dequeues the highest- (or lowest-) priority element first, regardless of insertion order, usually implemented with a heap. It models urgency-based processing.
Under the hood
Heap-backed versions give O(log n) insert and extract; central to scheduling and greedy algorithms.
Examples
Dijkstra, task schedulers, event simulation, bandwidth shaping.
Think of it like...
Like an ER treating the most critical patient next, not whoever arrived first.