পুল রিকোয়েস্ট এবং কোড রিভিউ কী?

A PR proposes merging a branch (e.g. a feature) into another (e.g. main):
  → shows the DIFF (what changed), a description, and discussion
  → reviewers comment, request changes, or approve
  → CI runs automated checks (tests, linting, builds) on the PR
  → once approved + checks pass → MERGE into the target branch
→ It's a gate and collaboration point before code is integrated.