# 5 Real-World Applications of the Stack Data Structure

The stack data structure is a fundamental concept in computer science and is used in a variety of real-world applications. From web browsing to undo/redo functionality, understanding how the stack works can help you better understand how these applications function.

In this article, we’ll explore the basics of the stack data structure and its practical applications.

## Web Browsing History

One of the most common uses of the stack data structure is in web browsing history.

As you navigate through different web pages, each page is added to the top of the stack. When you click the back button, the most recently visited page is removed from the top of the stack and displayed. This allows you to easily navigate back through your browsing history in a linear fashion.

Without the stack data structure, web browsing history would be much more difficult to implement.

## Undo/Redo Functionality

Another real-world application of the stack data structure is in undo/redo functionality.

When you perform an action in a program, such as typing a sentence or moving an object, that action is added to the top of the stack. If you want to undo that action, the program simply removes the most recent action from the top of the stack and reverses it. If you want to redo the action, the program adds it back to the top of the stack and performs it again.

This allows users to easily undo and redo their actions without having to manually keep track of every change they make.

## Call Stack in Programming Languages

The call stack is another important use of the stack data structure in programming languages.

When a function is called, it is added to the top of the call stack. As the function executes, any additional functions called within it are also added to the top of the stack. Once the function completes, it is removed from the top of the stack and the program returns to the previous function on the stack.

This allows programs to keep track of where they are in the execution process and ensures that functions are executed in the correct order.

## Expression Evaluation in Mathematics

The stack data structure is also used in expression evaluation in mathematics.

In this application, the stack is used to keep track of operators and operands in an expression. As the expression is evaluated, operands are pushed onto the stack, and when an operator is encountered, the necessary operands are popped off the stack and the result is pushed back onto the stack. This process continues until the entire expression has been evaluated and the final result is at the top of the stack.

This method allows for efficient and accurate evaluation of complex mathematical expressions.

## Backtracking in Algorithms

Backtracking is a common problem-solving technique used in algorithms, and the stack data structure plays a crucial role in its implementation.

Backtracking involves exploring all possible solutions to a problem by incrementally building a solution and then undoing or “backtracking” when a dead end is reached. The stack is used to keep track of the current state of the solution being built, allowing for easy backtracking when necessary.

This technique is used in a variety of applications, such as solving puzzles and finding optimal paths in a maze.