Git Interview Questions

git fetch downloads new commits and updates remote-tracking branches like origin/main without touching your working branch. git pull runs a fetch and then integrates the changes into the current branch, by merge by default or by rebase if configured. Fetching first lets you inspect before integrating.

A conflict happens when both branches changed the same lines or one deleted a file the other edited. Run git status to list conflicted files, edit each to combine the changes and remove the markers, run tests, then git add and continue the merge or rebase. Use --abort to back out safely.

Merge joins histories with a merge commit and rewrites nothing. Rebase replays your commits on a new base, producing a linear history but new commit SHAs. Never rebase commits others have based work on, such as a shared branch or main; rebase your own local feature branch, and merge into shared ones.

git revert creates a new commit that undoes an earlier one, so it is safe on shared branches. git reset moves the branch pointer back, with --soft, --mixed or --hard deciding what happens to staged and working changes; use it only on unpushed commits. git restore discards file changes. git reflog recovers mistakes.

Use git bisect: mark a known bad commit and a known good one, and Git binary-searches the range, so 200 commits need about eight checks. Automate it with git bisect run and a script that exits 0 for good, 1 for bad and 125 to skip untestable commits. Make the check deterministic first.