Please note that the content of this book mainly consists of articles that are available online from Wikipedia or other free sources. Bariatric surgery refers to surgical procedures aimed at combating pathological obesity (adiposity). There are a number of procedures: in addition to gastric banding and Mason or Eckhout gastroplasty, where a large part of the stomach is stapled with a four-fold stapler, there are also various bypass techniques. While gastric banding and gastric plastic surgery aim to limit food intake (referred to as restrictive techniques), the various gastrointestinal bypass techniques also have a malabsorptive effect, meaning they restrict the metabolism of the ingested food. The Roux-en-Y bypass is primarily considered restrictive with a malabsorptive component.