I'm barely able to get the idea, so I'm going to explain it poorly.
Imagine two dimensions: Width and height. Like a piece of paper. Now if you put them side by side one way, they're joined lengthwise (1 dimension) but not heightwise (the other dimension). You can also do that in reverse.
There are at least 8 dimensions. We're generally only capable of perceiving four: 3 dimensions and time.
Places can have some dimensions in common and not others, like the papers. Or like sticking something to one facet of a cube.