By Walter S. Mossberg
The World Wide Web is a marvelous thing. Because it exists, more people have direct access to more knowledge than at any time in history. But, by linking people everywhere, the Web has also spawned a new international criminal class, and a related class of sleazy businesses.
These creeps now find it easier than ever to defraud people, steal their identities and blast them with unwanted or false advertising. They use the Web as a pathway to infect computers, corrupt data and take over others' machines.
Security software can help block this wave of woe. But it would be better to know in advance if a Web site that comes up in a search result, or one you arrived at through other means, is harboring malicious software, or perpetrating scams, or generating spam and unwanted pop-ups. It might also be nice to know if a site with an innocuous name contains pornography, hate speech or other content that might be offensive to you.
I've been testing two services that aim to provide such advance notice of bad or offensive sites. The services, Scandoo and SiteAdvisor, take different approaches to the task and offer different features. But both instantly mark up a search-result page, and label the links that might be dangerous.
Both services are free of charge, and each works on both Windows and Macintosh computers, and in multiple Web browsers. On balance, I prefer SiteAdvisor, though Scandoo has a couple of things SiteAdvisor lacks.