Ooui (pronounced weee!) is a small cross-platform UI library for .NET that uses web technologies. It presents a classic object-oriented UI API that controls a dumb browser. With Ooui, you get the full power of your favorite .NET programming language plus the ability to interact with your app using any device. Make sure to add a reference to Ooui before you start running! With just code, a web server that serves the HTML and web socket logic necessary for an interactive button will start. Ooui has been broken up into several packages to increase the variety of ways that it can be used. When the user requests a page, the page will connect to the server using a web socket. This socket is used to keep the server's in-memory model of the UI (the one you work with as a programmer) in sync with the actual UI shown to the user in their browser. This is done using a simple messaging protocol with JSON packets.