IIS - Internet Information Services
Internet Information Services, formerly called Internet Information Server, is a Microsoft web server software application created for use with Microsoft Windows. It is the web server used by .NET services and websites. The latest version of IIS supports HTTP, HTTPS, FTP, SMTP etc.
Internet Information Services is a technology integrated in the latest Windows server which provides easy-to-manage, security-enhanced and reliably hosting web applications and web services. It is the Microsoft-centric competition to Apache, the most popular web server used with Unix and Linux based systems.