Git Internals

Tree Objects and Snapshots

Explain how tree objects encode directory structure and why commits represent full snapshot trees.

The short version

Explain how tree objects encode directory structure and why commits represent full snapshot trees.

Key ideas

  • A tree records paths, modes, and child objects
  • A commit points to a root tree
  • Snapshot thinking is closer to how Git really works than a patch-only mental model

Why this helps you understand commands

Many command differences that feel arbitrary become easier once you see how Git is updating objects, refs, the index, or reachability.

Suggested follow-up

It pairs well with git show, git log --graph, git cat-file, git rev-parse, or git fetch.

Related Reads

Git Object Database

Understand blob, tree, commit, and tag objects, and why Git describes itself as a content-addressable object database.

Working Tree, Index, and Object Store

Separating the working tree, index, and object database is the clearest way to understand add, commit, restore, and reset.

Git References and HEAD

Put branches, tags, remote-tracking refs, and HEAD into one model so Git's pointer behavior becomes easier to reason about.

PreviousMerge Bases and Ancestry

Explain how Git uses common ancestors to reason about branch differences, merge inputs, and reachability.

NextBlob Objects and Content Addressing

Explain how blobs store raw content and why hashes become the identity of Git objects.