Pull request are not really a part of Git but are found really often in its workflow.
Pull requests show diffs, or differences, of the content from both branches. The changes, additions, and subtractions are shown in green and red.
As soon as you make a commit, you can open a pull request and start a discussion, even before the code is finished.
By using the mention system (something like @name) in the pull request message, you can ask for feedback from specific people or teams.
When the change have been imported, the branch is normally deleted.
Automatic rebase of a branch before a PR
git config branch.autosetuprebase local