AdvancedSockets is a C# library which contains easy-to-use classes for setting up your own http, socket or websocket server and client.
Arqan is an OpenGL library I wrote a long time ago. It basically pInvokes all OpenGL functions from c++ and converts it to a C# method. Both a Linux and Windows version is available as well as bindings to the popular GLFW library.
Arqanore is a 2D desktop game framework built on top of Arqan, hence the name is an extension. A few more classes have been provided prior to Arqan. This includes a class for a gamewindow, sprites, fonts, rendering, math, some utils and what not.