Pillbugs are common backyard inhabitants around the world. They are called pillbugs because they can roll like an old-fashioned (pill pic). Pillbugs are closely related to the snowbug. They are also similar in shape but ones a little flatter but they can’t roll up. Pillbugs are crustaceans creatures and are similar to crabs or lobsters. Pillbugs breathe through there gills and not through there lungs. Pillbugs are always a little moist and can be found in clamped places.