A convention's toastmaster is an odd creature, neither fish (a GoH) nor fowl (committee) but is usually a well-known fan or pro who provides a public face to major events such as the Hugo Ceremony (in the case of a Worldcon, the masquerade, opening ceremony, closing ceremony, and sometimes other events such as GoH speeches, etc. It is traditional for a convention to rarely, if ever, repeat a GoHship, but repeating toastmasters are common.
For many years, an important function of the toastmaster was presenting the Hugo awards. Some time in the 1990s, this practice changed to the current one of having the toastmaster introduce many othe rpeople who do the actual presenting of the awards. The first Worldcon to have this "Hollywood" style Hugo ceremony may have been LoneStarCon 2 in 1997.
