Node.js developers are free to worry about the process crashing as it doesn't exist. Almost no functions in Node.js do I / O directly, so the process never hangs. Therefore, it is very conducive to develop scalable systems in Node.js.
Node.js framework is similar in design and influenced by systems like Ruby's Event Machine and Python's Twisted. But Node.js takes the event model a bit further. It includes an event loop as an execution runtime instead of a library.