Etherpad is a highly customizable open source online editor providing collaborative editing in really real-time.

Etherpad is a highly customizable open source online editor that provides real-time collaborative editing in the user’s browser. It supports over 105 languages and has thousands of instances worldwide, with millions of users. The platform allows for documents to be edited collaboratively in real-time, much like a live multi-player editor, making it ideal for creating articles, press releases, to-do lists, and other documents. Etherpad is highly customizable through plugins, and its main development happens on GitHub. It’s an open-source project with contributions from passionate developers worldwide.