Basically Visual Studio 2010 SP1 adds support for IIS Express
IIS Express is a free version of IIS 7.5 that is optimized for developer scenarios:
- It’s lightweight and easy to install (less than 5Mb download and a quick install)
- It does not require an administrator account to run/debug applications from Visual Studio
- It enables a full web-server feature set – including SSL, URL Rewrite, and other IIS 7.x modules
- It supports and enables the same extensibility model and web.config file settings that IIS 7.x support
- It can be installed side-by-side with the full IIS web server as well as the ASP.NET Development Server (they do not conflict at all)
- It works on Windows XP and higher operating systems – giving you a full IIS 7.x developer feature-set on all Windows OS platforms
