In computer science, a stack is an Abstract data type that serves as a collection of elements, with two main principal operations:

  1. Push, which adds an element to the collection, and
  2. 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 (last in, first out). Additionally, a peek operation may give access to the top without modifying the stack.

[links added]

(“Stack (Abstract Data Type)” 2022)

References

“Stack (Abstract Data Type).” 2022. Wikipedia, June. https://en.wikipedia.org/w/index.php?title=Stack_(abstract_data_type)&oldid=1091819102.