Tags are labels that you can add to Splitgraph images. A tag is unique per-repository.
There are two reserved tags,
latest always points to the most recent image
in a given repository. If you have checked out at least one image in a repository,
to the image you checked-out. If you have not checked out an image, or you have just created the
HEAD points to the "empty image" (hash
You can manage image tags using the
sgr tag command.