Re: for newbs = little exercise / tutorial / warmup for windows and other non-sophisticated new Git users :-)

> branches in most SCMs). In git, a branch is a mutable pointer to a commit,
> which is the latest commit on the branch (all of the earlier commits on
> the branch are linked off of the latest one; each commit points to the one
> before). By default, you have a branch called "master", and that's the
> branch that your series of commands builds up. Now, at any given time, you
> can have a "current branch" (a.k.a. HEAD), which is the branch that you'd
> put a new commit on if you made one. "master" is your current branch while
> you're building up that history.

> When you want to navigate the history, however, you want to leave all of
> the branches alone and take your working directory into the history. This
> is known as being on "(no branch)" or, as Zippy would say, having a
> "detached HEAD". This way you leave the "master" branch pointing to
> versionD, which is, after all, the latest commit, while you get yourself
> an old version. You can do this with:

> $ git checkout versionA
>
> because you've made a tag for it. In order to get back to developing (as
> opposed to looking at history), you use:
>
> $ git checkout master
>
> (because "master" is your branch, while "versionA" is a tag).
>
> If you're on master, either after checking it out explicitly or before
> you've used checkout at all, doing:
>
> $ git checkout versionA .
>
> with *not* switch you away from the current branch, but will get the
> contents of "." from versionA into your index and working directory, and
> it doesn't remove things that you have currently.