What is the role of a queue data structure and in what situations is it used?

A queue is a data structure that operates on the FIFO (First In, First Out) principle, meaning the first element entered is the first to be removed.

Role of a queue:

• Organizing ordered storage and processing of data.
• Managing tasks or events in the order they arrive.

Use cases:

• Processing requests in web servers.
• Scheduling tasks in operating systems.
• Implementing buffers in data streams.
• Asynchronous processing of messages and events.

Example in Java using a queue:

import java.util.LinkedList;
import java.util.Queue;

Queue<String> queue = new LinkedList<>();
queue.add("Task 1");
queue.add("Task 2");

while (!queue.isEmpty()) {
    String task = queue.poll(); // retrieves and removes the first element
    System.out.println("Processing: " + task);
}