What Does Git Commit Do? Understand Its Role

May 4, 2025

Ever wonder how developers track every change in their code? The git commit command is the cornerstone of version control that makes this possible. It creates a permanent snapshot of your files in the Git repository, capturing a moment in your project’s evolution.

Whether you’re a beginner learning Git basics or an experienced developer refining your Git workflow, understanding what does git commit do is essential for effective software development.

This command transforms temporary changes into permanent records in your project’s version history, complete with commit messages that explain why changes were made. Think of commits as checkpoints you can always return to.

In this guide, we’ll explore everything about the commit process—from basic usage to advanced techniques—helping you master this fundamental Git command and improve your development workflow.

You’ll learn how to create meaningful code snapshots that document your project’s journey and facilitate collaboration with other software developers.

What Does Git Commit Do?

Git commit is a command that records changes to a repository. It saves the current state of the project, including added or modified files, into the project’s history. Each commit creates a unique snapshot, allowing developers to track progress, revert to previous states, and collaborate more effectively.

Anatomy of a Git Commit

maxresdefault What Does Git Commit Do? Understand Its Role

Understanding the structure of a Git commit helps you work more effectively with version control and make better decisions about your code management. Let’s break down what makes up a commit in the Git software.

Core Components

Every commit in your local repository contains these essential elements:

Commit hash – A unique SHA-1 identifier that serves as the commit’s fingerproof. This Git reference looks like 8a7d15f8b8a58202217593dd0ec16622d5b6e19c and is how Git tracks your revision history.
Author information – Contains details about who made the change, including name and email address. This helps track code contributions across your development team.
Timestamp – Records exactly when the code snapshot was created, establishing a clear project timeline for your version history.
Commit message – A human-readable description explaining what changes were made and why. Writing good commit descriptions is crucial for effective source control.

Git stores this data permanently. Once created, the commit becomes part of your project’s code history.

The Commit Tree Structure

Commits don’t exist in isolation. They form interconnected nodes in a development workflow graph.

Each commit (except the initial one) points to at least one parent commit, creating parent-child relationships. This structure is fundamental to how source code management works in Git.

A → B → C → D  (main branch)
      ↘
        E → F  (feature branch)

This tree structure enables powerful Git workflow features like branching and merging. When you create branches, you’re essentially making different paths through this commit tree, which can later be combined.

The Staging Area

The staging area (or index) serves as a preparation zone before committing code.

When you use git add, you’re moving changes from your working directory to this staging area. Files here are ready to be included in your next commit.

Working Directory → Staging Area → Repository
   (modified)        (staged)       (committed)

This intermediate step gives you control over exactly what gets included in each commit, allowing you to:

Group related changes together
Keep unrelated changes in separate commits
Review what will be committed

Understanding this relationship between staged changes and commits is essential for creating a clean commit history that properly documents your project’s evolution.

The Git Commit Command in Practice

The git commit command is where version control actually happens. Let’s look at how to use it effectively as part of your software development process.

Basic Usage Syntax

The simplest form of the command is:

git commit -m "Your message here"

Common Git commit options include:

-m – Specify a commit message inline
-a – Automatically stage and commit all modified tracked files
--amend – Modify the most recent commit
--no-edit – Reuse the previous commit message

You can combine flags for more control:

git commit -am "Fix login bug"

This command is powerful but deceptively simple. It creates a permanent code snapshot in your project’s history that can be referenced by its commit ID.

Writing Effective Commit Messages

Your commit message is crucial documentation. It should clearly explain:

What changes were made
Why they were made (the purpose)

Follow these commit guidelines:

Use the imperative mood (“Add feature” not “Added feature”)
Keep the first line under 50 characters
Add a blank line followed by more detailed explanation if needed
Reference issue numbers if applicable

Conventional commit formats provide structured templates like:

feat: add user authentication
fix: correct date calculation bug
docs: update installation instructions

Using consistent commit naming makes your Git log more readable and useful for team collaboration.

Committing Files

You can control exactly what gets included in your commit:

Adding specific files using git add <filename> before committing
Committing all changes with git commit -a
Partial file commits using git add -p to select specific hunks

This granular control is one of Git’s most powerful features. It lets developers create atomic commits that contain only related changes, making your commit history more useful for:

Code review
Troubleshooting
Understanding project evolution

Remember that you can always view what will be committed using git status before executing the commit command.

Mastering these fundamental aspects of Git commits will significantly improve your development workflow and collaboration with other developers. A well-structured commit log serves as both documentation and a safety net for your project.

Advanced Git Commit Operations

Once you’ve mastered basic Git commands, it’s time to explore advanced commit operations that enhance your software development workflow. These techniques give you finer control over your repository.

Amending Commits

Made a mistake in your last commit? No problem. The --amend flag lets you modify your most recent commit without creating a new entry in your version history.

git commit --amend -m "New improved message"

This command replaces the previous commit with a new one, allowing you to:

Fix typos in your commit message
Add forgotten files
Make small adjustments to code

Remember that amending changes the commit hash, essentially creating a new commit that replaces the original. Never amend commits that have been pushed to a shared repository unless you’re working alone. This alters Git history and causes problems for teammates.

When should you use --amend?

For local fixes before pushing
When you spot a minor issue right after committing
To combine forgotten changes with the previous commit

Interactive Commits

For precise control over what goes into each commit, the interactive mode is invaluable:

git commit --interactive

This opens a menu allowing you to:

Choose specific files to stage
Review changes before committing
Split changes within files into separate commits

The more targeted approach for selecting changes within files is:

git add --patch

This displays each modified section (hunk) and lets you decide whether to include it. You’ll see options like:

y – stage this hunk
n – don’t stage this hunk
s – split the hunk into smaller pieces
e – edit the hunk manually

Using these tools creates cleaner, more logical commits that make your code history easier to understand. Each commit should represent one logical change, following the principle of atomic commits.

Signing Commits

In team environments, security matters. Signed commits verify that code changes came from a trusted source.

git commit -S -m "Secure feature implementation"

The GPG verification process:

You create a GPG key pair
Configure Git to use your key
Add the -S flag when committing
Others can verify your commits are authentic

GitHub, GitLab, and Bitbucket all support verified commits, showing a “Verified” badge next to properly signed entries. This adds a layer of security to your development workflow, ensuring that code changes are legitimate and come from the expected authors.

Commit History Management

Managing your commit history effectively is crucial for long-term software development. A well-maintained history makes troubleshooting and collaboration much easier.

Viewing Commit History

The git log command is your window into the past:

git log

This displays a reverse chronological list of commits in your repository. Each entry shows the commit hash, author, date, and commit message.

For a more compact view:

git log --oneline

Customize your view with powerful options:

--graph – Show an ASCII graph of the branch structure
--stat – Include changed files statistics
--author="Name" – Filter by specific author
--since="2 weeks ago" – Show recent commits only

These visualization tools help you understand the evolution of your project and track changes over time. They’re essential for software engineers working in complex codebases.

Finding Specific Commits

Need to locate a particular change? Git offers several search methods:

git log --grep="bug fix"

This searches commit messages for the specified text.

To find changes that modify certain code:

git log -S"function_name"

This command, known as the “pickaxe” search, finds commits that add or remove the specified string.

For particularly challenging bugs, the git bisect command helps you locate the exact commit that introduced a problem:

Start the bisect process: git bisect start
Mark the current state as bad: git bisect bad
Mark a known good commit: git bisect good <commit-id>
Git will check out a commit halfway between good and bad
Test your code and mark it good or bad
Repeat until Git identifies the problematic commit

This binary search approach can save hours of debugging in large projects.

Reverting and Resetting Commits

Sometimes you need to undo changes. Git provides two main approaches:

Git revert creates a new commit that undoes the changes from a previous commit:

git revert a7d9c0e

This is safe for shared branches as it doesn’t alter history—it adds a new commit that counteracts an earlier one.

Git reset moves your branch pointer to a different commit, effectively removing later commits from history:

git reset --hard a7d9c0e

The --hard flag updates both the staging area and your working directory to match the specified commit.

Be extremely cautious with reset --hard as it can cause permanent data loss. Never use it on commits that have been pushed to a shared repository unless you’re deliberately rewriting public history.

For safer options:

git reset --soft – Moves the pointer but leaves your changes staged
git reset --mixed (default) – Unstages changes but preserves them in your working directory

Understanding these commit management tools gives you complete control over your project’s history. They’re essential skills for any developer working with Git version control, especially in team environments where clean history facilitates better collaboration.

Git Commit in Team Environments

Working with Git in teams requires consistency and clear communication. How you structure your commits directly impacts collaboration efficiency.

Commit Standards and Conventions

Teams need shared commit message standards. Without them, your commit log becomes chaotic.

Most successful development teams adopt conventions like:

Prefix-based formats that indicate the change type:

feat: add user authentication flow
fix: resolve date calculation error in reports
docs: update API documentation
test: add unit tests for payment processor

Issue reference requirements that connect commits to tickets:
```
[PROJ-123] Fix memory leak in image processor
```

Body structure guidelines for complex changes:

Subject line (50 chars max)

Detailed explanation of what changed and why.
Include multiple paragraphs if needed.

Fixes #42

Standardized commit patterns benefit your team by:

Making the commit history scannable
Enabling automated release notes generation
Improving code review efficiency
Facilitating easier debugging

Some teams implement these standards using commit hooks that validate messages before accepting them. Tools like Commitizen help developers follow these patterns reliably.

Code Review and Commits

Well-structured commits make code review substantially easier. They separate logical changes, making problems more visible.

Best practices for commits during code review:

Keep commits small but complete. One feature, one bug fix, one improvement.
Don’t mix unrelated changes in a single commit.
Use commit message to explain “why” not just “what” changed.
Respond to review feedback with new commits rather than amending existing ones.

When reviewers suggest changes, create follow-up commits with clear messages:

Address review feedback: improve error handling
Fix indentation issues per review comments

These can be squashed later if needed, but keeping them separate during review helps track progress. After approval, many teams use squash merges to maintain a clean main branch history while preserving detailed commits during development.

Git Commit Performance and Best Practices

How you structure your commits affects both repository health and team productivity. Optimizing your commit strategy leads to better outcomes.

Commit Size and Frequency

Should you make large or small commits? How often should you commit?

Small, frequent commits typically work best because they:

Make debugging easier with git bisect
Create more useful commit history
Reduce merge conflicts
Make code reviews more manageable

A good rule: if you can’t summarize what changed in one sentence, your commit is probably too big.

However, don’t commit incomplete work that breaks the build. Each commit should represent a complete, testable state—even if the feature isn’t finished.

Creating a rhythm of regular commits throughout your workday keeps your changes incremental and focused. Some developers follow practices like:

Commit after completing each subtask
Use timed intervals (commit every hour)
Never leave uncommitted work overnight

Technical Considerations

Commits affect repository performance and storage needs. Be mindful of:

Repository size: Large binary files in commits dramatically increase repository size. For these file types, consider:

Git LFS (Large File Storage)
External asset management
Selective file tracking with .gitignore

Commit compression: Git uses compression to store commits efficiently. Text files compress well, but frequently modified binaries don’t.

Rebase vs. merge: Rebasing keeps history linear and readable but requires extra care in team settings. Merging preserves complete history but creates more complex commit graphs.

Workflow Optimization

Atomic commits form the foundation of an optimized Git workflow. An atomic commit:

Contains only related changes
Doesn’t break the build
Includes all related tests and documentation
Makes one logical change

This approach creates a commit history that documents project progress clearly. Each commit tells a coherent story about why a change was made.

Consider these commit best practices:

Write messages in present tense, imperative mood
Start with a verb: “Add”, “Fix”, “Update”, “Remove”
Use consistent capitalization and punctuation
Reference issues/tickets where applicable
Keep subject lines under 50 characters
Include more details in the body when needed

Add password strength indicator

- Shows visual feedback on password requirements
- Updates color based on strength (red/yellow/green)
- Displays specific missing requirements

Fixes #297

Perfect your commit frequency by finding the right balance. Too few commits make changes hard to understand; too many fragment the story of your work.

Think of your commit history as documentation for future developers (including your future self). Each entry should help someone understand what changed and why, creating a useful narrative about how your project evolved over time.

Advanced teams might adopt techniques like commit squashing before merging to create a pristine main branch while preserving detailed development history in feature branches. This combines the benefits of frequent local commits with a clean public history.

By following these principles, your team will develop a Git workflow that enhances collaboration, maintains code quality, and creates a valuable historical record of your project.

FAQ on What Does Git Commit Do

What exactly does git commit do?

Git commit creates a permanent snapshot of your staged changes in the local repository. It records a point in your project’s version history with a unique commit hash, timestamp, author information, and descriptive message. This action doesn’t affect the remote repository until you use git push.

How is git commit different from git add?

Git add moves changes from your working directory to the staging area, preparing them for a commit. It’s like boxing items for shipping. Git commit takes those staged changes and permanently records them in the repository. These commands work together in the Git workflow: stage first, then commit.

What’s the proper way to write a commit message?

A good commit message begins with a concise subject line (under 50 characters) in imperative mood (“Add feature” not “Added feature”). For complex changes, add a blank line followed by a detailed explanation. Many teams follow conventional commit formats like feat: or fix: prefixes.

Can I undo a git commit?

Yes. For local commits, use git reset HEAD~1 to remove the last commit while keeping changes. For pushed commits, use git revert <commit-hash> to create a new commit that undoes previous changes. The command you choose depends on whether the commit history has been shared.

How often should I commit my code?

Commit whenever you complete a logical unit of work. Small, frequent commits create a more useful version history and make code review easier. Aim for atomic commits that represent one complete change rather than many unrelated modifications. This creates clearer project documentation.

What happens if I commit without a message?

Git opens your default text editor for you to enter a commit message. If you save with an empty message, the commit is aborted. Using git commit -m "" with empty quotes also fails. Commit messages are mandatory since they provide crucial context for version control.

How do I see what I’m about to commit?

Use git status to see which files are staged. For a detailed view of changes, use git diff --cached to see exactly what content will be included in your commit. These commands help you verify your code snapshot before finalizing it in your version history.

Can I commit only part of a file?

Yes. Use git add -p (or --patch) to interactively select specific changes within files. This lets you create more focused commits by choosing which “hunks” of code to include. It’s useful for separating unrelated changes in the same file, creating a cleaner commit history.

What’s the difference between commit and push?

Git commit records changes in your local repository only. Git push sends those committed changes to a remote repository (like GitHub or GitLab). Think of commit as saving a document locally and push as uploading it to the cloud for others to access.

How can I modify my last commit?

Use git commit --amend to change your most recent commit. This can add forgotten files or fix a commit message. It creates a new commit hash, replacing the previous one. Only amend local commits, as amending pushed commits can cause problems for collaborators.

Conclusion

Understanding what does git commit do transforms how you approach code versioning. This fundamental operation creates meaningful checkpoints in your source control that document your project’s evolution. Each time you commit, you’re not just saving changes—you’re building a comprehensive development timeline that tells the story of your code.

The power of Git commands lies in their deliberate workflow. Good commit practices lead to:

Cleaner project history that makes debugging easier
More effective collaboration through clear code contributions
Ability to track when and why changes occurred
Freedom to experiment knowing you can return to previous states

Mastering commit options and writing meaningful messages isn’t just about following conventions—it’s about creating useful documentation automatically as you work. Whether you’re a solo developer or part of a larger team using GitHub or GitLab, how you structure your commits directly impacts your productivity and the maintainability of your codebase.

Remember that each commit hash represents a complete snapshot of your project at a specific moment. Make those moments count.

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Bogdan Sandu

Bogdan is a seasoned web designer and tech strategist, with a keen eye on emerging industry trends.

With over a decade in the tech field, Bogdan blends technical expertise with insights on business innovation in technology.

A regular contributor to TMS Outsource's blog, where you'll find sharp analyses on software development, tech business strategies, and global tech dynamics.