The Reactor Pattern in Node.js
It is a concept of non-blocking I/O operations in Node.js. Through this pattern, we get the handler (or callback function) for each I/O operation. Each I/O request is submitted to a demultiplexer, that handles concurrency and queues the requests/events. Reactor pattern consists of resources, event notifier/demultiplexer, event loop, event queue, request handler.