The Visual Studio Development Server option applies only when you are running (testing) the Web project in Visual Studio. Production Web applications always run under IIS.
To specify the Web server for a Web site project
- In Solution Explorer, right-click the name of the Web site project for which you want to specify a Web server, and then click Property Pages.
- In the Property Pages dialog box, click the Start Options tab.
- Under Server, click Use custom server.
- In the Base URL box, type the URL that Visual Studio should start when running the current project.
Note: If you specify the URL of a remote server (for example, an IIS Web application on another computer), be sure that the remote server is running at least the .NET Framework version 2.0.
To specify the Web server for a Web application project
- In Solution Explorer, right-click the name of the Web application project for which you want to specify a Web server, and then click Properties.
- In the Properties window, click the Web tab.
- Under Servers, click Use Visual Studio Development Server or Use Local IIS Web server or Use Custom Web server.
- If you clicked Local IIS Web server or Use Custom Web Server, in the Base URL box, type the URL that Visual Studio should start when running the current project.
Note: If you clicked Use Custom Web Server and specify the URL of a remote server (for example, an IIS Web application on another computer), be sure that the remote server is running at least the .NET Framework version 2.0.
(Source: https://msdn.microsoft.com/en-us/library/ms178108.aspx)