A stack is a linear data structure that follows the Last-In, First-Out (LIFO) principle. This means that the last element added to the stack is the first one to be removed.

Understanding Stacks with a Real-Life Analogy

Imagine a stack of books on a table. When you add a new book, you place it on top of the stack. When you want to remove a book, you take the topmost book first. The last book you added is the first one you take out—this is how a stack works.