Mono Project is an Open Source implementation of the various ECMA and .NET framework technologies for Unix, Mac OS X, and Windows. The project includes a compiler, a class library, and a CLI runtime engine.
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New C# 3.0 features: variable type inference (the "var" keyword), anonymous types, array type inference, object initialization, collection initialization, and automatic properties. AOT now provides some support for 2.0 assemblies.
