It seems every one has an opinion on clowns, you either like them or not.  There are many different reasons why a person may not like clowns, a bad experience as a child, scary movie featuring a clown, or as one expert says clowns can make people feel uneasy because they can't tell what they really are because they are hiding behind a mask and a costume, makeup and false emotions. That's pretty deep, I think they just don't like the way they look. The first clowns on record were ancient, 5th Dynasty of Egypt ancient, that's one old clown. Some of the more popular clowns in the United States are the Hobo, Tramp and Bumb clowns, with their tattered clothes and dirty face, not so scary. In fact some of the more famous 'Character Clowns' who were very famous were the likes of Emmett Kelly, Harold Lloyd, Buster Keaton, Red Skelton's 'Klem Kadiddlehopper', and the most famous, Charlie Chaplin. Ronald McDonald is a clown and he's not scary, maybe kids relate to him because he represents Happy Meals and chicken nuggets, which I would be more afraid of the nuggets than the clown.  The fear of clowns is very real, Coulrophobia, the fear of clowns can cause panic, increased heartbeat, nausea, sweating and crying, hey I get those symptoms at every family reunion. In my book the scariest clowns, in order. The clowns from the movie,"Killer Clowns From Outer Space", "Pennywise The Clown" from Stephen King's book and movie" It", and last but not least, the clown that came alive in the movie 'Poltergeist'. Yes these scared the crap out of me, though overall I'm not afraid of clowns I wouldn't invite them over for a BBQ.  You don't have to watch a movie or go to a circus to get scared, if you want to see a bunch of clowns all in one place, go to Olympia or Washington DC, these clowns are for real, that's what makes them so scary.