If you are reading this book, you're probably an ASP.NET developer. However, even if you aren't, the Rails versus ASP.NET diatribe that's raised every so often in online forums and groups is worth addressing before wrapping up this "philosophical" chapter.
The "versus" question is often asked by developers who'd like to learn the "next big thing" in Web programming, be prepared for the evolution of the job marketplace, or, even more commonly, by programmers who're looking for the best tool for a certain project.
Becoming proficient in a new framework can take at least a few months, so it is understandable that most people don't want to bet "on the wrong horse."
Choices exist that are bound to become more popular and that better suit certain types of projects or development philosophies, just like there are options that are more productive than others. Switching to Rails from an ASP.NET background makes a lot of sense in most cases, so this section will help you to better understand how these two different frameworks compare from a macroscopic perspective.
From a technical standpoint Microsoft ASP.NET and Ruby on Rails are very different. They have so little in common that, at a microscopic level, a detailed list of differences would be huge. It is truly comparing apples to oranges; they are both round fruit, just like Rails and ASP.NET are both Web application frameworks, but they don't have too much in common ...