Hefeweizen is a type of weissbier -
beer that uses both
wheat malt and
barley malt for
fermentation, unlike most beers being made exclusively from barley malt. Hefeweizen additionally uses
yeast, which gives it a cloudy, translucent look.
There are several different styles of hefeweizens: leichtes weissbier (light wheat beer), dunkles weissbier (dark wheat beer), kristall weizen (filtered wheat beer),
Berliner weisse (low
alcohol wheat beer) or weizenbock (wheat beer with high
alcoholic content).
There are a number of different ways to pour a hefeweizen, but the most important thing to remember is that when you think you're finished pouring, you're not. There's still a thick, yeasty section that never comes out without a fight. The method I have seen to pour the remaining contents of a bottle is to place it on its side, then roll it back and forth with the palm of your hand on a smooth surface (say, a
bar).