It’s been a hot summer of self-driving car news. Ford announced it’s skipping over Level 3 and will put a fleet of Level 4 autonomous vehicles on the road in 2021. Mobileye and Delphi promised Level 4/5 self-drivers by 2019. Tesla’s talking about improving its Level 2 cars. Sounds exciting—if you have any idea what those numbers mean. Even when they’re using words, automakers obfuscate what their cars can do. Also floating in this stew of jargon are terms like autonomous, self-driving, semi-autonomous, and self-piloting.

Those driving levels come from the National Highway Traffic Safety Administration and SAE (formerly the Society of Automotive Engineers), which each have their own system. They’re nearly identical, but in the name of internationalism, we’ll use SAE’s. So, as cars that drive themselves evolve and spread over the coming years, here’s a guide for understanding what’s left for you to do.