It turns out that, whether it's Waymo's self-driving cars or the many auto manufacturers relying on tech from Intel Corp.'s INTC -1.27% Mobileye, so-called "autonomous" vehicles are cheating, in a way. This is also true of models that are already commercially available, such as Cadillacs with Super Cruise. Rather than perceiving the world and deciding on the fly what to do next, these autonomous and semi-autonomous vehicles are comparing their glimpses of the world with a map stored in memory. The incredibly detailed maps they rely on are what engineers call a "world model" of the environment. The model contains things that don't change very often, from the edges of roads and lanes to the placement of stop signs, signals, crosswalks and other infrastructure.