How Git Works Internally

›Very Simple English, No Heavy Words

Most people think Git is just this:

Type command → Save code → Done

But inside, Git is doing many smart things.

Git is not magic.

It is a system that stores snapshots, connects data, and protects history.

Let’s go inside Git and see how it really works.

What is the .git Folder?

When you run:

git init

Git makes a hidden folder:

.git

This folder is the brain of Git.

It stores:

• All commits
• All branches
• All file data
• All history

If you delete .git:

• Your files stay
• But Git forgets everything

So:

Your code = your project

.git = memory of your project

git-folder-structure

Git Objects: Blob, Tree, Commit

Git saves everything as objects.

›Blob

Blob means file data.

• Only file content
• No file name
• Same content = same blob

›Tree

Tree is like a folder.

• Connects file name to blob
• Connects folder to another tree

Tree says:

This name → This blob

This folder → This tree

›Commit

Commit is a full photo of your project.

It stores:

• One main tree
• Parent commit
• Time and author
• Message

So:

Commit = snapshot of your project

git-commit-tree-blob

How Git Tracks Changes

Git does not track lines.

It tracks full snapshots.

Every commit is a full picture.

If a file is same:

• Git reuses old blob

So Git saves space and time.

What Happens in git add

When you run:

git add file.txt

Git does:

1. Reads file
2. Makes hash of content
3. Saves it as blob in .git/objects
4. Adds it to staging area

So:

git add = prepare file for commit

What Happens in git commit

When you run:

git commit -m "msg"

Git does:

1. Reads staging area
2. Makes trees from folders
3. Links blobs to trees
4. Creates commit object
5. Moves branch to new commit

So:

git commit = save snapshot forever

git-workflow

How Git Uses Hash

Hash is like ID of data.

• Same data → same hash
• Small change → new hash

Git uses hash to:

• Name objects
• Find objects
• Protect data

If data breaks, hash will not match.

So Git knows something is wrong.

Simple Mental Picture of Git

Do not think in commands.

Think like this:

• git add = get ready
• git commit = save photo
• Commit = photo
• Branch = line of photos
• .git = photo album

Git is just:

• Data
• Hash
• Snapshots
• Pointers

Once you see this,

Git becomes simple.