Node.js

Node.js is a free, open-source runtime environment that lets programs written in JavaScript run on servers and computers rather than only inside a web browser. It was released in 2009 by Ryan Dahl and is built on Google's V8 JavaScript engine. Node.js uses an event-driven, non-blocking design: instead of waiting for each file read or network request to finish, it moves on and handles the result when it arrives, which suits applications that juggle many connections at once, such as chat services, payment webhooks and price feeds. Its package manager, npm, hosts a very large library of reusable code. In finance and crypto, Node.js is common for building an API, trading bots and wallet back ends, and much Ethereum developer tooling runs on it. It is distinct from a blockchain node, despite the similar name.