Crabs have ten legs and walk sideways very quickly. They can live in the water and on the beach. They have a hard shell, and two of their legs have pincers. This is the Japanese spider crab. It's the biggest crab in the world, and it can sometimes grow to nearly four meters wide. I Answer the questions. How many legs does a crab have? How do crabs walk? Where do crabs live? How do they protect themselves? What is the biggest crab in the world? What color are Japanese spider crabs? How big can Japanese spider crabs grow? e Does the crab in the picture have big pincers?