What are all the user accounts for IIS/ASP.NET and how do they differ?

Under Windows Server 2008 with ASP.NET 4.0 installed there is a whole slew of related user accounts, and I can’t understand which one is which, how to they differ, and which one is REALLY the one that my app runs under. Here’s a list: IIS_IUSRS IUSR DefaultAppPool ASP.NET v4.0 NETWORK_SERVICE LOCAL SERVICE. What is what? … Read more