堆栈（英语：stack），也可直接称栈。堆叠（，在计算机科学中，是一种特殊的串列形式的数据结构，它的特殊之处在于只能允许在链结串列或数组的一端（称为堆叠顶端指标，英语：top）进行加入数据（英语：push）和输出数据（英语：pop）的运算。另外堆叠也可以用一维数组或链表的形式来完成。堆叠的另外一个相对的操作方式称为队列。

由于堆叠数据结构只允许在一端进行操作，因而按照后进先出（LIFO, Last In First Out）的原理运作。

堆叠数据结构使用两种基本操作：推入（push）和弹出（pop）：

In computer science, a stack is 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 that was not yet removed. The order in which elements come off a stack gives rise to its alternative name, LIFO (for last in, first out). Additionally, a peek operation may give access to the top without modifying the stack.