SourceTree is a free Mercurial and Git Client for Windows and Mac that provides a graphical interface for your Hg and Git repositories. Developed by Atlassian
License: Free
TortoiseGit is a lightweight and customizable Git client primarily for Windows users, offering deep integration with the Windows Explorer, making it suitable for advanced users managing large repositories. On the other hand, SourceTree provides a more user-friendly experience with visual commit history and issue tracking integration, making it ideal for beginners and users seeking a comprehensive GUI for Git.