In node.js "non-blocking" implies that its IO is non-blocking. Hub utilizes "libuv" to deal with its IO in a stage skeptic way. On windows, it utilizes fulfillment ports for UNIX it utilizes epoll or kqueue, and so forth. In this way, it makes a non-blocking demand and upon demand, it lines it inside the occasion circle which calls the JavaScript 'callback' on the fundamental JavaScript string.
