First, to understand this deal it’s important to understand Facebook. Unfortunately everything about Facebook defies logic. In terms of user experience (insider jargon: “UX”), Facebook is like an NYPD police van crashing into an IKEA, forever — a chaotic mess of products designed to burrow into every facet of your life. The company is also technologically weird. For example, much of the code that runs the site is written in a horrible computer language called PHP, which stands for nothing you care about. Millions of websites are built with PHP, because it works and it’s cheap to run, but PHP is a programming language like scrapple is a meat. Imagine eating two pounds of scrapple every day for the rest of your life — that’s what Facebook does, programming-wise. Which is just to say that Facebook has its own way of doing things that looks very suspect from the outside world — but man, does it work.