About

The user originally for Git is the author.

Author vs Committer

But Git knows two persons:

• the author: the person who originally wrote the code / the patch.
• the committer: the person (project maintainer or core member) who committed the code or applied the patch on behalf of the original author.

You can therefore:

• rewrite history
• or apply patches

on behalf of another person.

Note that both get credits as an author and as a committer.

Example of workflow between an author and a committer

The patches :

• are generated by the author:
  • git format-patch, sent by email, either by copying and pasting,
  • or git send-email
• are applied by the committer with either git apply or git am generating a single new commit with a different author and committer.