Definition: Windows V2.8.1, commonly known as "Vista", was a popular Windows operating system released in 2006 by Microsoft. It introduced significant updates, features like Internet Explorer 9 for better browsing, but also included security patches to prevent common vulnerabilities. The term "Windows v2.8.1" comes from the fact that it had a version number of 2 and an update number of 8 (though this number doesn't actually reflect the release date).