It’s not about coffee here. Rather, Cappuccino is the path I chose for the future of interactive HTML without Flash, running on any modern browser without plugins. JavaScript (not to be confused with Java) is required, but that’s what any web-2.0+ page needs anyway.
Cappuccino is an open source framework, available at github, a solid foundation, allowing to to build desktop-caliber applications that run in a web browser, only relying on HTML5 and JavaScript. This is accomplished in two ways: (1) by “Objective-J” (a superset of JavaScript), a language very similar to Objective-C, and (2) by re-implementing a sizeable part of Apple’s NS* and CG* frameworks.
I liked Objective-C anyway, so using Objective-J was no big problem, and the NS* and CG* frameworks allow for a rich user interface with a consistent and fluent look-and-feel. If you have experience developing for Macintosh or iOS, you are nearly there.
All browsers now have implemented the “same-origin policy” (Wikipedia). If you want to run the Cappuccino demos from disk, you need to “allow cross origin requests”, which can be enabled in Safari, Firefox, Chrome, … (web search for your preferred browser).
Cappuccino is a major open-source endeavour which relies on a wonderful & select group of developers. Learning it requires a sizeable effort, yet is highly rewarding. I thank that community for creating and continuing development of this marvelous tool:
In 2011 I had started a list here, but at ≈100 this seemed a moot effort. Just start with the first :) and the button “Built with” will tell you. Also my vision test FrACT₁₀ is now built upon it.