Web of Trust (WOT) is a service that compiles ratings on millions of websites. These ratings help you know if you can safely use a website you’ve never encountered before, or trust it with your personal information. With virus, malware and phishing attacks rampant on the internet, there is a real need for this type of service.
The ratings in the service are based on a number of sources of information, including whether the site is getting social links and whether it has been blacklisted by anti-virus companies. But the biggest component of the ratings, according to the service, are votes by users of the service. It is a classic use of crowdsourcing – a vast unpaid team of volunteers (the users of the service) help make it better through their contributions. To avoid potential for abuse, the software uses a Bayesian algorithm to factor in user reputations and other factors.
For convenience, the WOT ratings are available through a web browser add-on, available for Firefox, Chrome, Internet Explorer, Safari, Opera and other browsers. It is compatible with Windows, Mac OSX and Linux operating systems.
Once it is installed in your browser, the add-on flags hyperlinks in many web pages with little round icons. Green for good, yellow for unsatisfactory and red for poor. So even before you click, you can see that where there might be a problem. This works on most normal web pages including Google results pages, Wikipedia pages and so on. It has recently been updated to support Twitter and Facebook (with their common use of shortened URLs) as well.