GameHosts (GHs) are the liaison between GM's and the players when it comes to technical issues in the game. They are the basic "frontline" in the chain of Customer Service.
They are required to have a good knowledge of the game and should be able to answer questions about basic technical issues and general gameplay. Hosts can also get involved in planning large-scale roleplaying events with GMs, acting as "extras" or "cast members" at special events and festivals, and sometimes helping to test out new systems and game mechanics for the GM staff.
Above from Official Website
GameHosts answer assists.