Web of Trust (WOT) is a free and open-source Web security product made by WOT Services, Ltd., of Finland. It has been described as a "crowdsourced website reputation service" that helps to provide certain kinds of Web filtering and security analysis for users.
Web of Trust is openly available for download on the Internet and is compatible with many different browsers and operating systems. It is used as an add-on for Firefox, Chrome, Internet Explorer, Opera and Safari.
The developer offers WOT as a system for taking Web security beyond basic antivirus and firewall systems, and for protection against online threats that require additional security measures.
Web of Trust works on the basis of a "red, yellow, green" traffic light system that is easy to understand from an end-user perspective.
Open-source crowdsourcing tools like this one are helping companies and other users to protect themselves from the high degree of illegal and harmful activity on the Internet and from various kinds of cyberattacks and data breaches.