Opera isn't exactly something that one simply adopts as a hobby at random. For many people it's a bit of an aquired taste, which is why the Denver Public Library offers its ongoing Opera 101 series to the public. The monthly meetings are free, and offer previews of current productions by Opera Colorado and the Central City Opera, along with discussions about plots, characters and classic performances of other operas. Tonight at 7 p.m., join in for a preview of the Metropolitan Opera's upcoming live radio broadcasts. The meeting will be held in the B2 Conference room of the Central Library.