Plumbing vs Porcelain

Objects Are Immutable

Lightweight vs Annotated Tags

Packed vs Unpacked Refs

Detached HEAD State

Loose Objects vs Packfiles

What Blobs Store

Trees and Directory Structure

Content-Addressable Storage

Commit Parent Pointers

What the Index Tracks

Git's Four Object Types

Compression and Deduplication

The Commit DAG

What a Ref Points To

Purpose of the Reflog

Plumbing vs Porcelain Commands

Git's Object Database and Object Lookup

Data Integrity via Hash Chaining

Loose Objects vs Packed Objects

Packfiles and Object Compression

Object Deduplication and Shared Blob Storage

Inside Git's Index (Staging Area)

References and the refs/ Namespace

The DAG: Commits as a Directed Acyclic Graph

Commit Object Anatomy

How Trees Represent Directory Structure

Loose Objects vs Packfiles

Git Config Levels (system/global/local)

The Reflog Mechanism

Parent Commits and Merge Commits Linkage

Tree Objects

Blob Objects

Lightweight vs Annotated Tags

Tag Objects (Annotated Tags)

The Commit Graph (DAG) Structure

Detached HEAD State

Immutability of Git Objects

Git Object Model Overview

The Object Database (.git/objects)

Commit Objects Internal Structure

Object Compression and Delta Storage

Refs and the refs Directory

The .git Directory Structure

Plumbing vs Porcelain Commands

Content-Addressable Storage in Git

Git's Four Object Types

Inside the .git Directory