Differentiate git clone vs fork, and merge vs rebase.
Quick Answer
Clone copies a repo to your local machine; fork copies it to your own remote account (for contributing to projects you cannot push to). Merge combines branches preserving history with a merge commit; rebase replays your commits onto another base for a linear history.
Detailed Answer
Fork + pull request is the open-source contribution model; clone is just getting a working copy. Merge is non-destructive and keeps the true history (good for shared branches); rebase rewrites commit history for a clean, linear log (good for tidying your own feature branch before merge). The golden rule: never rebase commits that others have already pulled.
Interview Tip
End with the golden rule of rebase — do not rebase shared/pushed history — it is the follow-up interviewers ask.