A beekeeper puts extra boxes on top for the bees to fill with honey. Those boxes are called supers. The very same type of box can be used as brood chamber or as a super. The name refers to what the bees use it for.
The Tardis is a horizontal hive body. It's the same size as two boxes side by side. We love that arrangement because when you take the lid off, it's easy to see inside and you can see all of the brood chamber at once without worrying about accidentally killing the queen when you're taking one brood box off the other.
The box on the bottom is all one box. There are two boxes stacked on top, under the lid. This gives the bees plenty of space for honey but the smaller boxes will be easier for us to lift. Honey is heavy!
Notice they like the left one better. It's the original one.