You can learn a lot from the rind of a cheese.
There are three types of rind: Bloomy, washed, and natural. While I don't think it is technically a rind I would also list waxed as a category.
Bloomy rinds are formed when molds and such that grew during the cheese aging are smashed flat. Usually such cheeses will have unique textures because of the action of the mold. Think of the creaminess of brie as an example. The rind is edible if it is in good condition.
Washed- the cheese is wiped with vinegar or similar while it ages.
Natural- The top layer of the cheese is allowed to dry as the cheese ages. Parmesan is a good example of this.
Waxed- Wax is applied to inhibit drying and mold growth. It is common with many semi firm to firm cheeses and doesn't tell you much except the favorite color of the cheese marketing people. Cheddar is almost always waxed.
Some cheeses don't have a rind at all- this generally means that they weren't aged. Cream cheese, queso fresco are examples. Mozarella and feta are both brined and so don't have rinds.
Of course- it is a good thing when you can see any rind at all as odds are good that the cheese wasn't mass produced for an undiscriminating clientele.