Node was created in late 2009 by Ryan Dahl. Based on Chrome's V8 engine, Node provides a JavaScript runtime built for the purpose of providing evented, non-blocking I/O (input/output) for serving web applications.

At the time, Chrome had created the fastest JavaScript engine available. At the same time, they had decided to open-source the code for it. For these two extremely compelling reasons, Node decided to use the V8 engine.

Ryan Dahl was unhappy with the performance, at the time, of the very popular Apache HTTP server. One of the problems with the way that Apache was handling concurrent connections was that it was creating a new thread for each connection. Task creation and task switching between these threads are both CPU-and memory-intensive. For these reasons, instead of using threads for concurrent connections, Dahl decided to write Node with the intent of using an event loop coupled with a callback paradigm.