I'd thought you were kidding as well, but I realize you're pretty new here. Ruby on Rails is the most popular web framework for startups in Silicon Valley, fol

I'd thought you were kidding as well, but I realize you're pretty new here. Ruby on Rails is the most popular web framework for startups in Silicon Valley, followed by Django, and then PHP. High-profile companies that primarily use Rails: Airbnb, Square, Github, and Twitter (for Twitter some of their codebase is in Scala; for Airbnb, they're also doing a lot with node.js. Both companies started out as Rails apps). I also ran the numbers a while ago on the web framework breakdown for YC startups. The breakdown is something like (give or take 10%): 60% Rails, 20% Django, 5% non-Django Python, 3% Sinatra (also Ruby), 3% Node.js, 3% PHP, 6% don't know, If you want to learn a web framework/technology, Ruby on Rails or Django is definitely the place to start.