Discourse is a free and open-source Internet forum software. Features include support for categorization and tagging of discussions, configurable access control, live updates, expanding link previews, infinite scrolling, and real-time notifications. It allows for a high level of customizability via its plugin architecture and its theming system. It was released on August 26, 2014, by its founders, Jeff Atwood, Robin Ward and Sam Saffron. Since its release, Discourse has been undergoing active development with over 40,000 commits as of March 2022.