An abstract data type that serves as a collection of elements, with two principal operations: push, which adds an element to the collection, and pop, which removes the most recently added element.

"Stacks are used in algorithms and programming to store data temporarily in a way that it can be retrieved in Last-In-First-Out order."

A data structure that stores elements in a last-in, first-out (LIFO) manner, where elements are inserted and removed from the same end, often used for function calls, expression evaluation, and backtracking.

"The function call stack kept track of the order of function calls and their local variables."