# Which Data Structure Is Also Known as FIFO?

//

Heather Bennett

Which Data Structure Is Also Known as FIFO?

A data structure that is commonly referred to as FIFO is a queue. In computer science, a queue is an abstract data type that follows the First-In-First-Out (FIFO) principle. This means that the first element added to the queue is the first one to be removed.

## What is a Queue?

In simple terms, a queue can be envisioned as a line of people waiting for their turn. The person who arrives first gets served first, and as new people arrive, they join the line at the end. Similarly, in programming, a queue allows elements to be added at one end (the rear) and removed from the other end (the front).

## Operations on a Queue

A queue typically supports two main operations:

1. Enqueue: This operation adds an element to the rear of the queue.
2. Dequeue: This operation removes and returns the element from the front of the queue.

The enqueue operation increases the size of the queue by one, while dequeue decreases it by one. These operations maintain the order of elements within the structure.

### Implementation of a Queue

A common way to implement a queue is by using an array or a linked list. Arrays offer constant time access to elements but require shifting all subsequent elements when deleting from the front. Linked lists allow for efficient insertion and deletion at both ends but require extra memory for storing pointers.

Here’s an example implementation using an array:

````<!-- HTML code -->`
<script>
// JavaScript code
class Queue {
constructor() {
this.queue = [];
}

enqueue(element) {
this.queue.push(element);
}

dequeue() {
return this.shift();
}

size() {
return this.length;
}
}

// Usage example
const queue = new Queue();
queue.enqueue(10);
queue.enqueue(20);
queue.enqueue(30);

console.log(queue.dequeue()); // Output: 10
</script>
```

## Common Applications of Queues

Queues find applications in various areas, including:

• Process scheduling algorithms in operating systems.
• Buffer management in network communication.
• Handling requests in web servers.

The FIFO nature of queues makes them suitable for scenarios where the order of processing or handling is critical.

### Conclusion

A data structure that follows the First-In-First-Out (FIFO) principle is known as a queue. It allows for efficient insertion and removal at opposite ends, making it useful for various applications such as process scheduling and network communication. By understanding the fundamentals of queues, developers can leverage them to build efficient and organized systems.