Stacks

The stack is a widely used LIFO structure (last-in-first-out-last-in-first-out) in many programming languages. This design is called "stack" because it looks like a real stack, a stack of plates. It also provides the following additional functions for checking the status of the stack for example - 

• Peak: Displays the top of the stack without emptying the stack.
• isEmpty: Checks if the stack is empty.
• IsFull: Checks if the stack is full.

Stacks are used for evaluating batch expressions such as mathematical field algorithms for parsing and evaluating formulas and are also used to implement function calls in recursive programming.