Web of Trust (WOT) is a simple add-on which shows you via traffic lights which websites you can trust for safe surfing, shopping and searching on the web.
WOT ratings are powered by users of the extension that have rated millions of websites based on their experiences. Other third-party sources are also used to warn you about malware and other technical threats.
The warning process is simple. You see a green, yellow or red icon next to search results when you use Google, Yahoo!, or Bing, on links in social networking sites like Facebook and Twitter, on online email services such as Gmail, Yahoo! Mail and Hotmail. It also includes several other popular sites such as Wikipedia. Green is trustworthy, yellow mean cautious and red means a potentially unsafe site.
You can change settings to decide where you want to see ratings, and whether you want to be warned of potential danger. You can also share your experiences by rating sites yourself thus adding to the community. There's not much to fault with WOT although it is possible that some sites will be flagged as dangerous when they are in fact OK. However, most of the time, its very accurate.
WOT is an excellent extension that keeps you safe when browsing the web.