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+* COR: [Common Object Runtime](http://www.danielmoth.com/Blog/mscorlibdll.aspx). The name of .NET before it was named .NET.
+* DAC: Data Access Component. An abstraction layer over the internal structures in the runtime.
+* EE: Execution Engine.
+* PAL: [Platform Adaptation Layer](http://archive.oreilly.com/pub/a/dotnet/2002/03/04/rotor.html). Provides an abstraction layer between the runtime and the operating system
+* SOS: [Son of Strike](http://blogs.msdn.com/b/jasonz/archive/2003/10/21/53581.aspx). The debugging extension for DbgEng based debuggers. Uses the DAC as an abstraction layer for its operation.
+* URT: Universal Runtime. Ancient name for what ended up being .NET, is used in the WinError facility name FACILITY_URT.
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