A user recently commented on Mozilla Add-ons that WOT is great, because it can be used to create a blacklist of our own. He’s right, it can. This is also how the basic phishing protection on your browser works. Your browser has a blacklist of malicious websites, which it updates every now and then. If you come across a website on the list, it will warn you. However, WOT is more than that, it also gives you the benefits of a whitelist.
Unlike a blacklist, a whitelist contains websites that are known to be good. In addition to warning you of bad sites, WOT also provides you with a positive indication if the website you are visiting has a good reputation. This is just as important as a warning. Because no blacklist is ever complete, having a whitelist to back it up makes the whole system more reliable. If WOT doesn’t suddenly know your bank’s website, it’s a sign that something is wrong, even if the blacklist on your browser hasn’t yet been updated to notice the scam.
More than a whitelist
The problem with whitelists has traditionally been that there are just too many websites. No single authority is capable of judging whether the sites are trustworthy. This results either in poor coverage or an unreliable whitelist. WOT solves this problem by letting you, our users, set the reputations. No single entity can know all websites, but in a large user community, there is a good chance that some people have prior experience with any single website.
However, WOT is not just a combination of a blacklist and a whitelist either. WOT reputations are on a linear scale. A simple binary system is not sufficient when measuring trust, because not all websites are entirely evil or completely trustworthy. With WOT, the world is not just black or white.