Git Essentials: What Happens Inside the .git Folder
When I first saw git it felt like magic, file change, commit appear and history preserved. But behind the scenes git follows a very simple and powerful model. Let's understand that in this article.
How Git Works Internally?
In simple terms, git is a content tracking system, not just a file tracker.
It takes snapshots of our Project.
Stores them efficiently.
links them together using cryptographic hashes.
Understanding The .git Folder
This is the brain of our Repository. If we delete this folder then git history is gone.
The inside .git folder
objects/ : Where get stores all data (files, folder, commits)
refs/ : Pointers to branches and tags
HEAD : Tells git which branch you are on.
Index : The staging area
Git Objects: Blob, Tree, Commit
git stores everything as objects.
Blob (file content)
Stores the content of the file.
No file name no path just raw data.
Same content = same blob (across even across files)
Tree (folder structure)
Represents the directory
Maps filenames to blobs
Defines how files are arranged
Commit (snapshot)
Points to one tree (the project state)
Stores metadata (author, message, time)
Points to the previous commit
How Git Tracks Changes
Git doesn’t store changes line by line. It stores new objects only when content changes.
Example:
You edit one file
Git creates a new blob for that file
Other unchanged files reuse old blobs
A new tree and commit are created
This is why Git is:
Fast
Reliable
What Happens During git add and git commit
git add
Read file’s content
Create blob objects
Updates the index
git commit
Reads the staging area
Creates a tree object
Creates a commit object
Moves the branch pointer forward
How Git uses Hashes for Integrity
Every git object is identified by a Hash. It depends on object content and object type.
It means:
when the content is changed the hash changes
Tampering is instantly detectable
History cannot be silently modified
This is how git ensures Integrity.
Closing Statement
Git feels like magic but knowing its internal makes you trust it confidently. When you know what's happening inside git folder it becomes Predictable and Powerful.