The document discusses the history and development of gonioscopy. It notes that gonioscopy was first visualized by Alexois Trantas in 1907 and Maximilian Salsmann in 1914 is considered the father of gonioscopy. It describes improvements to contact lenses and development of gonioprisms by Koeppe, Uribe Troncoso, Barkan, and Goldmann. The document provides details on various gonioscopy lenses and their uses. It discusses the advantages and disadvantages of direct vs indirect gonioscopy and classifications used to grade the iridocorneal angle.