1. What is "Git"?

Git is a distributed version control system (DVCS) designed to handle everything from small to very large projects with speed and efficiency. It allows multiple developers to work together on the same codebase.

2. What is "Version Control"?

The practice of tracking and managing changes to software code over time. It keeps a history of all modifications, allowing you to revert to earlier versions if something goes wrong.

3. What's the difference between "Git" and "GitHub"?

Git: A software tool installed on your computer for version control.
GitHub: A web-based hosting service for Git repositories.

4. What is a "Repository" (Repo)?

A data structure that stores the complete history of a project, including all files, directories, and their modifications.

5. What's the difference between "Centralized" and "Distributed" VCS?

Centralized: A single central server stores all versions of code (e.g., SVN). If the server goes down, history is lost.
Distributed: Every developer has a complete copy of the code and its history on their machine (e.g., Git).

6. What is "Cloning"?

The process of creating a local copy of a remote repository.

7. What's the difference between `git init` and `git clone`?

git init: Initializes a new Git repository in an existing directory.
git clone: Downloads an existing repository from a remote server to your computer.

8. What's the difference between "Staging Area" and "Working Directory"?

Working Directory: The files you are currently editing.
Staging Area: A middle ground where you "stage" (prepare) changes that you want to include in your next commit.

9. How do you "Commit" changes in Git?

Using the git commit command, which takes all changes currently in the staging area and records them as a permanent snapshot in the repository's history.

10. What is a "Commit Message"?

A short description that explains what was changed and why. Good commit messages are crucial for maintaining a clean project history.

11. What is a "Branch"?

A parallel version of the repository. It allows you to develop features, fix bugs, or experiment in isolation without affecting the main codebase (usually main or master).

12. How do you create and switch to a "New Branch"?

git branch <name>: Create a new branch.
git checkout <name>: Switch to the branch.
git checkout -b <name>: Create and switch in one step.

13. What is "Merging"?

The process of integrating changes from one branch into another (e.g., merging a feature branch back into the main branch).

14. What is a "Merge Conflict"?

Occurs when two different branches have made changes to the same line in the same file, and Git doesn't know which version to keep. You must resolve these manually.

15. What's the difference between `git merge` and `git rebase`?

git merge: Combines two branches by creating a new "merge commit." It preserves the branch history exactly as it happened.
git rebase: Replays your changes on top of another branch. It creates a cleaner, linear history but can be dangerous on public branches.

16. What is "Pulling" vs "Fetching"?

git fetch: Only downloads the latest changes from the remote without merging them into your local branch.
git pull: Downloads the changes and immediately tries to merge them into your current branch (equivalent to fetch + merge).

17. What is "Pushing"?

The process of uploading your local commits to a remote repository (e.g., git push origin main).

18. What is the `.gitignore` file?

A text file where you list the files and directories that Git should ignore and not track (e.g., node_modules, .env, log files).

19. What is "Head" in Git?

A reference to the currently checked-out commit or branch (the "current state").

20. What's the difference between "Soft", "Mixed", and "Hard" reset?

--soft: Moves HEAD back but keeps changes in the staging area.
--mixed: (Default) Moves HEAD back and moves changes to the working directory.
--hard: Moves HEAD back and deletes all changes (dangerous).

21. What is `git stash`?

Temporarily saves (stashes) your uncommitted changes so you can work on something else or switch branches without losing your work.

22. What is `git revert`?

Creates a new commit that undoes the changes of a previous commit. It's the safest way to "undo" something on a public branch.

23. What is `git log`?

A command that displays the commit history of the current branch.

24. What is `git diff`?

Shows the differences between two versions of a file, or between the working directory and the staging area.

25. What is "Forking" in GitHub?

Creating a personal copy of someone else's repository on your GitHub account so you can make changes without affecting the original project.

26. What is a "Pull Request" (PR)?

A request sent to the original project's owner to merge your changes from your fork or branch into their codebase.

27. What is "SSH" vs "HTTPS" for remote URLs?

HTTPS: Uses username/password or personal access tokens; accessible through firewalls.
SSH: Uses cryptographic keys; no password needed after setup; more secure.

28. What is "Remote"?

A version of your repository that is hosted on the internet or another network (e.g., origin).

29. What is `git remote -v`?

Lists the URLs of the remote repositories currently associated with your local project.

30. What is "Tagging" in Git?

Giving a specific name to a specific point in the project's history (e.g., v1.0.0), usually for release versions.

31. What is the difference between "Lightweight" and "Annotated" tags?

Lightweight: Just a pointer to a commit.
Annotated: Stored as full objects with a name, email, date, and message.

32. What is `git cherry-pick`?

The process of applying a specific commit from one branch to another without merging the whole branch.

33. What is "Main" vs "Master" branch?

They are the same thing (the default branch). GitHub and Git have moved to using "main" as the default name.

34. What is "Fast-Forward Merge"?

Occurs when the target branch has no new commits since you branched off. Git simply moves the pointer forward.

35. What is "Recursive Merge"?

A more complex merge strategy used when the branches have diverged (both have new commits). It creates a new merge commit.

36. What is `git checkout -- <file>`?

A command (in older Git versions) to discard local changes in a specific file and restore it to its last committed state. (Replaced by git restore).

37. What is `git branch -d` vs `git branch -D`?

-d: Deletes a branch only if it has been fully merged.
-D: Force deletes a branch even if it has unmerged changes.

38. What is `git remote add origin <url>`?

Connects your local repository to a new remote repository named origin.

39. What is "Git Flow"?

A branching model for Git that defines a specific set of branches (main, develop, feature, release, hotfix) to manage the development process.

40. What is `git reflog`?

A detailed log of all movements of the HEAD pointer. It's a lifesaver for recovering "lost" commits or branches.

41. What is "Detached HEAD" state?

Occurs when you checkout a specific commit instead of a branch. Changes made in this state will be lost unless you create a new branch.

42. What is a "Bare Repository"?

A repository that doesn't have a working directory. It's typically used on servers to share the code.

43. What is "Git LFS" (Large File Storage)?

An extension for Git that handles large files (like high-res images or videos) by replacing them with text pointers inside Git, storing the actual files on a separate server.

44. What is "Submodule" in Git?

Allows you to keep another Git repository as a subdirectory of your own repository, useful for shared libraries.

45. What is `git reset --hard HEAD~1`?

A command that deletes the most recent commit and all changes made in it.

46. What is `git blame`?

Shows which developer made which change to each line of a file.

47. What is `git show`?

Displays the detailed information and file changes of a specific commit.

48. What is "Hooks" in Git?

Scripts that Git executes automatically before or after specific events (like pre-commit, post-merge).

49. What's the difference between `origin` and `upstream`?

origin: Your own fork of a project.
upstream: The original project repository you forked from.

50. Why is Git so widely used?

Because it's fast, handles large projects easily, has a reliable distributed architecture, and provides powerful branching and merging tools.

Git Interview Questions

Table of Contents

What is "Git"?

What is "Version Control"?

What's the difference between "Git" and "GitHub"?

What is a "Repository" (Repo)?

What's the difference between "Centralized" and "Distributed" VCS?

What is "Cloning"?

What's the difference between <code>git init</code> and <code>git clone</code>?

What's the difference between "Staging Area" and "Working Directory"?

How do you "Commit" changes in Git?

What is a "Commit Message"?

What is a "Branch"?

How do you create and switch to a "New Branch"?

What is "Merging"?

What is a "Merge Conflict"?

What's the difference between <code>git merge</code> and <code>git rebase</code>?

What is "Pulling" vs "Fetching"?

What is "Pushing"?

What is the <code>.gitignore</code> file?

What is "Head" in Git?

What's the difference between "Soft", "Mixed", and "Hard" reset?

What is <code>git stash</code>?

What is <code>git revert</code>?

What is <code>git log</code>?

What is <code>git diff</code>?

What is "Forking" in GitHub?

What is a "Pull Request" (PR)?

What is "SSH" vs "HTTPS" for remote URLs?

What is "Remote"?

What is <code>git remote -v</code>?

What is "Tagging" in Git?

What is the difference between "Lightweight" and "Annotated" tags?

What is <code>git cherry-pick</code>?

What is "Main" vs "Master" branch?

What is "Fast-Forward Merge"?

What is "Recursive Merge"?

What is <code>git checkout -- &#x3C;file></code>?

What is <code>git branch -d</code> vs <code>git branch -D</code>?

What is <code>git remote add origin &#x3C;url></code>?

What is "Git Flow"?

What is <code>git reflog</code>?

What is "Detached HEAD" state?

What is a "Bare Repository"?

What is "Git LFS" (Large File Storage)?

What is "Submodule" in Git?

What is <code>git reset --hard HEAD~1</code>?

What is <code>git blame</code>?

What is <code>git show</code>?

What is "Hooks" in Git?

What's the difference between <code>origin</code> and <code>upstream</code>?

Why is Git so widely used?

What is <code>git checkout -- <file></code>?

What is <code>git remote add origin <url></code>?