What is a queue and how does it differ from a stack?

A queue is a linear data structure following First-In-First-Out (FIFO) principle where elements are added at the rear and removed from the front. Unlike a stack (LIFO), a queue processes elements in the order they were added. Main operations are enqueue (add to rear), dequeue (remove from front), front (view first element), and isEmpty, all with O(1) complexity.