# What Data Structure Is FIFO?

//

Larry Thompson

Data structures are essential concepts in computer science and programming. They allow us to organize and store data efficiently.

One commonly used data structure is FIFO, which stands for First-In-First-Out. In this article, we will explore what FIFO is and how it works.

## What is FIFO?

FIFO is a method of organizing and manipulating a collection of elements where the first element added to the collection is the first one to be removed. It follows the principle of “first come, first served.” This concept can be visualized as a queue, where elements are added at the end and removed from the front.

## How Does FIFO Work?

To implement FIFO, we typically use a data structure called a queue. A queue allows us to add elements at one end, known as the rear or back of the queue, and remove elements from the other end, called the front or head of the queue.

Let’s imagine a scenario where customers are waiting in line at a bank. The first customer who arrives goes to the front of the line, while new customers join at the rear.

As each customer is served, they leave from the front of the line. This process continues until all customers have been served.

### Operations on a FIFO Data Structure

• Enqueue: Adding an element to the rear of the queue.
• Dequeue: Removing an element from the front of the queue.
• Peek: Viewing (but not removing) the element at the front of the queue.

### Example Code

To better understand how FIFO works in practice, let’s take a look at some example code in a common programming language like Python:

```  ```
class Queue:
def __init__(self):
self.queue = []

def enqueue(self, item):
self.queue.append(item)

def dequeue(self):
if not self.is_empty():
return self.pop(0)

def is_empty(self):
return len(self.queue) == 0

def peek(self):
if not self.queue[0]

queue = Queue()
queue.enqueue("Alice")
queue.enqueue("Bob")
queue.enqueue("Charlie")

print(queue.dequeue())  # Output: Alice
print(queue.peek())     # Output: Bob
```
```

In this example, we create a queue using a list and define the necessary methods to enqueue, dequeue, and peek at the elements. The enqueue method adds an item to the end of the list, while the dequeue method removes and returns the first item. The peek method allows us to view the first element without removing it.

## Conclusion

FIFO is a fundamental data structure that follows the principle of first-in-first-out. It can be visualized as a queue where elements are added at one end and removed from the other. Understanding FIFO and its implementation using a queue data structure is crucial for efficient data management in various applications.

By incorporating FIFO into your coding arsenal, you’ll be equipped to handle scenarios where order matters and ensure fair treatment of data elements based on their arrival time.