Queueing in Node.js is a vital technique for efficiently managing asynchronous operations, which are central to the language's non-blocking nature. In Node.js, queues help organize tasks such as HTTP requests, file operations, and streams, all of which can have variable completion times due to the nature of asynchronous processing. Node.js relies on several types of callback queues, such as the IO queue for input/output tasks, the timer queue for time-related tasks, the microtask queue for process.nextTick and promises, the check queue for immediate execution tasks, and the close queue for tasks associated with close events. The event loop is responsible for managing these queues by continually checking and executing queued functions based on their priority, which ensures that asynchronous operations are handled smoothly. Understanding how these queues and the event loop work together helps developers effectively manage asynchronous processes in Node.js, enabling the creation of responsive and efficient applications.