Greetings! Today, we're unveiling the concept of Stacks in Ruby, a fundamental data structure. Imagine a stack as a pile of dishes: you add a dish to the top (Last In) and take it from the top (First Out). This Last-In, First-Out (LIFO) principle exemplifies the stack. Ruby handles stacks effortlessly with Arrays. This lesson will illuminate the stack data structure, operations, and their Ruby applications. Are you ready to start?

A stack is a storage structure that allows Push (addition) and Pop (removal) operations. It's akin to a stack of plates in a cafeteria, where plates are added (pushed) and removed (popped) from the top. No plate can be taken from the middle or the bottom, exemplifying a Last-In, First-Out (LIFO) operation.

To create a stack, Ruby employs a built-in data structure known as an Array. For the Push operation, we use push, which adds an element at the end of the array. For the Pop operation, there's the pop method that removes the last element, simulating the removal of the 'top' element in a stack. Here's how it looks: