Bazaar, whose command-line tool is bzr, is a distributed version-control system sponsored by Canonical, the company behind Ubuntu. Its project page on Launchpad, Canonical’s own development hosting platform, describes it as “a friendly powerful distributed version control system” that works by “recording the history of the project, providing an easy means to copy the history around, and making it easy to merge changes between projects.”
The project was registered in 2005, the same year that git and Mercurial appeared, and grew out of Canonical’s earlier work on version-control tooling. Bazaar was written in Python and, fittingly, used Bazaar itself for its own development. It later became part of the GNU System.
A central design goal was ease of use. Bazaar served as the primary version-control system for Launchpad and was the tool many Ubuntu contributors used to record history and merge changes between branches. The Launchpad page frames the system around helping development teams “work together” by making project history easy to copy and merge.
Like several distributed systems of its era, Bazaar was eventually overtaken by git’s dominance and is now largely historical, though it remains a notable part of the distributed version-control story and of how a major Linux distribution organized its collaboration.