IIS Express is installed automatically when you install Visual Studio 2012 and Visual Studio 2013. If you want to install IIS Express in Visual Studio 2010 (SP1 is required), you can use the Microsoft Web Platform Installer (https://www.microsoft.com/web/gallery/install.aspx?appid=IISExpress).
source https://msdn.microsoft.com/en-us/library/58wxa9w5(v=vs.120).aspx#iisdisadvantages
source https://msdn.microsoft.com/en-us/library/58wxa9w5(v=vs.120).aspx#iisdisadvantages