You can use any email address in the git commit metadata. If you use Linus' email, Github shows the commit as created by Linus. If you want other people to be

You can use any email address in the git commit metadata. If you use Linus' email, Github shows the commit as created by Linus. If you want other people to be able to verify you actually created a commit/tag, git allows to sign objects with a PGP key.