One quick caveat: my extensive field research indicates that some specimens are cross-breeds of more than one of these types. And by "some specimens," I mean the dude behind me at a recent Nationals-Mets baseball game.

1) Captain Obvious – Guy who considers himself a real scholar of the game and provides a running commentary on it, but never says anything actually insightful. For example, the quarterback is 3-21 with four interceptions. "Boy, he's just not having a very good game today. Not at all." Thanks, Joe Theisman for that window into the inside world of
the NFL.

2) The Whiner – The dude/woman who just bitches about everything. The parking cost too much, the owner's too stingy/too profligate, the team should have done X, Y, Z, the old stadium was better.

3) The Ignoramus – Repeatedly makes comments about the match/game that belie a significant misunderstanding about the rules and/or strategy, such as the woman sitting behind me at a college football game who repeatedly exhorted the home team kicker to put the kickoffs out of bounds (for those unfamiliar, that's a five yard penalty). They believe that any play/pass/run into space that doesn't score/gain big yards/yield three runs was obviously a bad idea and that they could manage the team much better.

4) Mr. or Mrs. Fingernails on Chalkboard – Anybody whose voice is just inherently annoying to hear all game, especially if they do a lot of screaming. The girl behind me at a recent Nats - Braves game was like that, and she really topped it off by doing the tomahawk chop in that screechy voice. I considered telling her to stop her racist chanting, but her boyfriend was large and muscular, so I decided that the 8th inning at RFK was not the time or place for a roundtable on race relations and American sport.

5) Robin Williams – Somebody who thinks that they are very funny, and therefore tries to constantly make funny comments throughout the match. Of course, they are not funny. They're just eye-gougingly irritating. Like a bad morning DJ, every play on the field is greeted with some very unfunny trying-to-be-funny observation from him, at loud volume, which often includes references to his rec league sporting activities, such as his hall of fame career in the Henrico County Over-40 Mens's Rec "C" Softball League.

6) The Know-It-All – Close relative to The Ignoramus. Just pontificates at length about anything and everything remotely related to the game. Always has an opinion on everything, usually based on dubious logic or factual errors. These people are harmless as long as they're not really loud, but they're usually loud and hard to tune out.

7) Mr. Irrelevant – Somebody who prattles on throughout the game about stuff that has nothing or little to do with the business at hand. Often these people have their head turned to the people behind them, as they explain how Johnny is doing in his youth lacrosse league, as I pray to God that a foul ball/stray puck/wounded Canadian goose hits them in the back of the head.

8) Mad Max – Someone who just screams and shouts, often incoherently, at the coach, ref, etc. This is not to be confused with the classic art of creative heckling. This is one of those people that has really blown a gasket and proceeds to spread their bad mood throughout the crowd.

9) The Frat Dick – some guy, usually 18-25, who gets really drunk and belligerent, often starting physical confrontations with other fans, while maintaining the opinion that being obnoxious makes them cool.

10) The School Marm – This one is rare, but not unheard of. Somebody who constantly admonishes fans in their section for swearing, making noise during the national anthem, standing up for a key play, etc.

These people are out there, and in huge numbers. Be wary.