A browser extension can show these ratings on hyperlinks such as on web search results.

[1] The service was originally developed by SiteAdvisor, Inc, an MIT startup[2] first introduced at CodeCon on February 10, 2006,[3] and later acquired by McAfee[4] on April 5, 2006.

[5][citation needed] Sites are rated in levels of Safe (green tick), Suspicious (yellow exclamation mark) and Unsafe (red "X").

Malicious code and browser exploits often spread fast over large numbers of websites,[9] meaning a Green rating may not be up to date and may provide a false sense of security.

McAfee SiteAdvisor now makes use of the TrustedSource website reputation organisation, to act as something like a 'cloud' intelligence software to get the most up-to-date information on websites as possible, very similar to McAfee's Active Protection (Artemis) system.