 Version-control snapshot

A version-control snapshot records the logical state of tracked files at a revision. In Git, tree objects describe directory entries and refer to content objects; a version-control commit identifies the root tree alongside history metadata. Unchanged content can be shared among many version-control snapshots.^[ref]

If a repository contains a.txt and b.txt, changing only a.txt creates a new logical version-control snapshot containing the new a.txt and unchanged b.txt. It does not require a second physical copy of every byte. Two version-control commits can identify the same version-control snapshot but have different parents or messages. The recorded files and the ancestry explaining how they arose are therefore distinct information.