Git is a distributed version-control system that records snapshots of a project's files over time, letting many people or agents work on independent copies and later merge their changes back together.
Git tracks history as a graph of commits, each a snapshot of the entire project plus a pointer to its parent commit, rather than a list of line-by-line diffs. Because every clone carries the complete history, most operations — committing, branching, viewing history — happen locally and instantly, with no server round-trip required. Branches are lightweight, movable pointers to a commit, and merging combines the changes from two branch histories into one.
Created by Linus Torvalds in 2005 to manage Linux kernel development, Git has since become the dominant version-control system for software projects of nearly every size. Git itself is a command-line tool and protocol; the collaboration layer built on top of it — pull requests, code review, issue tracking — is provided by hosting platforms like 📝GitHub, not by Git itself.