Git is basically an object storage. Most objects in Git are blobs identified by their hash code. For example, a commit points to a directory. A directory points

Git is basically an object storage. Most objects in Git are blobs identified by their hash code. For example, a commit points to a directory. A directory points to all files and directories it contains. With this foundation, Git is already quite efficient in common scenarios since most commits create only a few new objects: the commit, the new versions of the files, and all directory nodes all the way to the top. Git could store all of these in the filesystem. Often, they are stored in indexed and compressed pack files though. But the underlying principle remains the same.