Welcome to the home of the book “Distributed revision control with Mercurial”, by Bryan O'Sullivan. This is a freely licensed book about the Mercurial revision control system.
Mercurial is a member of the Software Freedom Conservancy, a wonderful non-profit organisation that offers its member projects legal and administrative advice. The SFC can accept accept donations (tax-free under IRS 501(c)(3), within the United States) on behalf of its member projects. If you would like to support Mercurial directly, please consider making a donation to the SFC on its behalf.
If you would like to help free software developers to provide their important public services without being impeded by legal issues, please consider donating to the SFC's sister organisation, the Software Freedom Law Center.