Year 2000 marked a historic movement in the Server Editions of Microsoft when they released Windows Server 2000. This was the best and the biggest server technology Microsoft had ever released. For the first time, it introduced features like, Active Directory Structure, Active server pages and XML which revolutionized the web application development and hosting. It had three versions: The Server, Advanced Server, Data Centric Server.
Windows Server 2003
In the year 2003, Microsoft introduced Windows Server 2003 which encapsulated .NET framework for the first time. It improved the Active Directory Structure along with ASP with improved scalability. It had two versions; the standard enterprise version was geared to large companies and corporate sector while the web edition was simply for web hosting purposes. Few months after the release of Windows Server 2003, Microsoft introduced the support for 64 bit systems in Windows Server 2003 for the first time in any Windows Server Edition. References http://www.vtc.com http://en.wikipedia.org/wiki/Windows_Server