HipHop is the Open Source PHP language compiler and runtime designed and used by Facebook. HipHop offers a significant speed improvement over the official PHP runtime and supports most of its core features. This session will provide an introduction to how and why to use HipHop over PHP, and the benefits it offers. By even the most conservative estimates, at least 50% of all websites on the Internet are powered by PHP, a language with a long and robust history of Open Source development principles. And while PHP's virtual machine is extremely efficient at executing even the most "creative" scripts, it will simply never be able to compete with native code. HipHop bridges that gap by translating easy to develop PHP scripts into high-speed, low-impact native code which can double, or even triple, the capacity of every node in your front end. This drives down costs, and delivers faster content to users. But why, outside of Facebook and a few other installations, don't we see this taken advantage of? There are some differences between HipHop and PHP, notably in the breadth of runtime extensions and namespaces. Also, HipHop's documentation, while growing, still lags behind the massive body of work on php.net. If you run more than one webserver however, it'll be worth 50 minutes to see what HipHop has been up to since we first introduced it at FOSDEM, how much easier it is to run a HipHop server in both production and development modes, and a little bit of how it works under the hood.