As long as there have been bridges, trolls have hidden beneath them. Same for the Internet.

As long as there have been message boards, discussion groups, and comment strings, there have been "trolls" - people who, under cover of Web anonymity, post bullying, lewd, or off-point comments, disrupting and demeaning the whole enterprise. Some comment strings are moderated, so trolls can be blocked and deleted - but most of cyberspace is, in the words of one (anonymous!) wit, "free range for idiots."

Just one example, to stand for many, from a Harry Potter site: "ENOUGH already with all this Harry Potter [expletive]! What sort of LOSERS think this stuff is cool??? I swear, the little [indelicate term] should be carved up with rusty scythes and his remains poured into a cement mixer. I am so sick and tired of hearing about Harry [extreme epithet] [other extreme epithet] POTTER!"

It's been a problem for years. Julie Spira, an expert on Web etiquette and author of the book Netiquette, says, "It started with some of the early usenet groups, where some of the first 'flame wars' broke out among users."

Some sites - newspapers and entertainment venues - are so encrusted with trolls, like malign barnacles, that comment threads become all but useless. Jolie O'Dell, a reporter for the the tech-business blog VentureBeat, says: "I don't read comments anymore. I've learned there's nothing anyone's going to say that's going to meet me at a professional level of discourse."

Julia Hobsbawm, who runs the British media, analysis, and networking business Electronic Intelligence, says comment strings are "fertile ground for those who prefer to vent spleen rather than offer rigorous, fair, and balanced argument." Spira says: "There's no doubt that anonymity has turned the World Wide Web into the Wild Wild West."

People are looking for solutions. Some, like Gayle Lynn Falkenthal, media columnist for Washington Times Communities, have called for an end to anonymity. "And you should have seen the trollery after I did!" she says from San Diego. "It was jaw-dropping." She says she values the First Amendment, "but any venue with a public responsibility, such as a newspaper, a media site, anything with public money behind it - no place for anonymity there."

The last five years have seen the rise of what O'Dell calls "a new breed of employee called the 'community manager,' a big part of whose job is policing commentary, allowing for freedom of speech, but deleting profanities, offensive things, trollery." More and more venues are hiring community managers because they see their reputations tied to the quality of their online communities.

Where is the comment the smartest and best behaved? Much-copied moderated websites include the Huffington Post and Papers such as The Inquirer and the Wall Street Journal do not moderate comments, but other papers, such as the Boston Globe and the San Diego Union-Tribune, do.

Trollery has inspired much experiment. Chris Satullo, a former Inquirer editor who is executive director of news and public dialogue for WHYY, was a main force behind NewsWorks, the station's news site. NewsWorks has an admirably well-thought-out and explicit policy about comments, based on that of

When comments are removed, the producer of the page announces the move and explains why it was made. Satullo says it seems to work fairly well.

Spira and O'Dell praise the discussion platform Quora. "They've tied your reputation to how smart and substantive your comments are," says O'Dell. Spira likes how sites such as Quora "give users a stake in making the site work. Users are invested in the community and want to keep it clean and authentic."

Hobsbawm says that mere "peer pressure is often insufficient to self-regulate abusive comment strings," but she, too, likes media platforms that tie quality to attention.

Web-lovers are leery of all this policing and pressuring. But courtesy expert Spira says, "All of us can only gain if, when we comment, we stay on topic, show respect, and provide a new perspective on the subject that other users might find interesting."

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