Animal skins provides clothing for the Eskimos; their favorite is caribou because it is warm and lightweight. Lacking caribou they would settle for seal, polar bear, or even Arctic fox. Styles varies from area to area, but in all regions everyone wear the same combination: a hooded jacket, trousers or leggings, socks, boots, and mittens. Sometimes goggles made from wood or bone were worn. In winter two sets of clothes were used. The inner layer would have fur next to the skin. The second layer would have fur on the outside. Air between the two layers help keep body heat in and allowed perspiration to evaporate. A single layer is enough during summers.