Git is a free, open-source distributed version control system that tracks changes across a project history, lets developers branch and merge locally, and keeps a complete repository copy on every machine so work can continue offline and history can be audited later.
The official site offers downloads and installers for Windows, macOS and Linux distributions, the complete Pro Git book in several languages, command reference documentation, release notes and links to graphical clients and community learning resources.
It suits individual developers keeping a clean history, teams coordinating parallel feature work through branches and pull requests, and maintainers who need to bisect regressions, tag releases or recover earlier states of a shared codebase.
Compared with older centralised systems, branching is cheap and most operations are local; compared with a code hosting platform it is only the underlying tool, so review, permissions and automation are provided by the forge layered on top.
Learn the difference between merge and rebase before rewriting shared history, configure identity and line endings at the start of a project, keep a remote backup of important branches, and prefer revert over force-push on public branches.