So I have a C++ library which uses native bsd sockets that I'd written for some other client a while back. I want to use this in Unity too and access it to/from C## code. I assume I will have to write a native plugin and then interact with from Unity C# code. Its not something I've done before (I've written either only C++ or only managed code projects) so not sure how it works. Before I get started - I wanted to clarify what this page is trying to say http://docs.unity3d.com/Documentation/Manual/Plugins.html What does Pro/Mobile only mean here? Only the Pro/Mobile Unity builds can access my native plugin? I don't have Unity pro and want my access to my native library from all Unity targets (Web/Mobile/PC/Mac). Whats the best way to go? I took a look at https://github.com/fholm/udpkit to see how that works. It doesn't have a readme/steps for a beginner like me so I couldn't understand much from it. I'm sure its great for folks who are versed with working with native plugins from managed code. Also I am OK with using the C++ source directly if possible in Unity - I guess its not possible and it must be a compiled library.