Netflix Has 77K Movie Genres How one writer deconstructed the site's recommendation engine By John Johnson, Newser Staff Posted Jan 2, 2014 6:27 PM CST 9 comments Comments This screenshot shows some genre suggestions on Netflix. (Netflix) (Newser) – Have you ever gotten a really weirdly specific genre suggestion from Netflix? Something like, say, "Mind-bending Cult Horror Movies from the 1980s"? Well, Alexis Madrigal at the Atlantic got to wondering just how many genres Netflix had up its sleeve, so he created a script that would spam Netflix's URL and scrape them all. The result? Netflix has 76,897 genres that contain content, and more than 90,000 possible genres in the system. Each genre is constructed from some combination of possible content tags, arranged according to the following order heirarchy: Region + Adjectives + Noun Genre + Based On... + Set In... + From the… + About... + For Age X to Y. When Madrigal contacted Netflix about his findings, he got to talk to the man who created the system, Todd Yellin. He discovered that Netflix hired people to watch movies and catalog their attributes, including rating things like their romantic content on a 1-5 scale. The process is so precise that there's a 36-page training manual for doing this. A computer algorithm then creates more tags—movies with certain characteristics, like a happy ending, might automatically get a "feel good" tag. Netflix calls the entire process its "Quantum Theory," because it believes each movie's appeal can be broken into "quanta" or "packets of energy." For much, much more on the process—and the goofy genre generator Madrigal whipped up with his data, read the full story.