Internet Information Services (IIS) 7.5 is a technology included in Windows Server 2008 R2, which provides a security-enhanced, easy-to-manage web server for developing and reliably hosting web applications and web services. This enables organizations to deliver rich, web-based experiences.
IIS 7.5 is a major enhancement to the Windows web platform and plays a central role in unifying Microsoft web platform technologies—ASP.NET, Windows Communication Foundation web services, and Windows SharePoint Services.