git reset. again

This is shamelessly copied from the web archive.

Assume you start from a "everything is committed and golden" state. Let's pretend you came to this starting point via a git checkout: and then you edit a bunch of stuff, compile/test, and then git add and git commit:

$ git checkout mywork
...edit edit edit...
$ git add ...
$ git commit

If at this point you do a git reset, here's how the type of reset ("soft", "hard", or the default, which is "mixed") affects things:

$ git checkout mywork
            # --hard resets to this point
...edit edit edit...
            # --mixed (default) resets to this point
$ git add ...
            # --soft resets to this point
$ git commit

Also note, as gitster says, that git commit --amend makes the git reset --soft mostly redundant.