A Yule Goat or Julebuk is today a goat made out of hay and held together by red ribbon. Back in the days it was believed that the Julebuk was evil as it represented all the 'bad' things such as ghosts, misfortune and hell. Therefore it was treated with respect and sometimes even fed. The above is how my grandmother explained it to me but this specific Nordic tradition has changed a lot throughout the years. Before Santa Claus the yule goat had the role as the gift bringer and at one point a 'Julebuk' was instead a person dressing up as a goat and pranking people during christmas.
The Julebuk tradition is an example one one that is no longer very common at all. People still associate the hay figure with christmas and use them for ornaments, but there are no longer any certain rituals around them. Never the less I succeeded in making my little sister believe it was the mean Julebuk who had eaten her chocolates when we were kids...