Git merge vs rebase — when to use which

Team debates merge vs rebase. Inconsistent approach leads to messy history and painful conflicts.

Rules: (1) Rebase YOUR local branch onto main before merging — linear history. (2) Never rebase shared branches — rewrites history. (3) Merge for integrating features: git merge --no-ff feature. (4) Rebase for updating feature branch with main. (5) Squash merge for small features. (6) For releases: always merge. Golden rule: rebase local, merge shared.

Rebase rewrites history by creating new commits with different parents. Clean for local but destructive for shared branches. Merge preserves all original commits.