git clone origin-url (non-bare) : you will get all of the tags copied, a local branch master (HEAD) tracking a remote branch origin/master, and remote branches origin/next,origin/pu, and origin/maint. The tracking branches are set up so that if you do something like git fetch origin, they'll be fetched as you expect. Any remote branches (in the cloned remote) and other refs are completely ignored.
git clone --bare origin-url : you will get all of the tags copied, local branches master (HEAD), next, pu, and maint, no remote tracking branches. That is, all branches are copied as is, and it's set up completely independent, with no expectation of fetching again. Any remote branches (in the cloned remote) and other refs are completely ignored.
git clone --mirror origin-url : every last one of those refs will be copied as-is. You'll get all the tags, local branches master (HEAD), next, pu, and maint, remote branchesdevA/master and devB/master, other refs refs/foo/bar and refs/foo/baz. Everything is exactly as it was in the cloned remote. Remote tracking is set up so that if you run git remote update all refs will be overwritten from origin, as if you'd just deleted the mirror and recloned it. As the docs originally said, it's a mirror. It's supposed to be a functionally identical copy, interchangeable with the original.
