There is a Leopard Seal, Harp Seal, Gray Seal, Harbor Seal, Northern Elephant Seal, Southern Elephant Seal, Weddell Seal, Hawaiian Monk Seal, Mediterranean Monk Seal, Antarctic Fur Seal, Galapagos Fur Seal and Northern Fur Seal. And if you want to know what is the biggest seal in the world, then it's the Southern Elephant Seal!