It's actually quite complex to unpack. In the past, you could order the cars with or without FSD hardware (on promises of future capability). These days (~202

It's actually quite complex to unpack. In the past, you could order the cars with or without FSD hardware (on promises of future capability). These days (~2020+? I'm not sure the cutoff), you can order them without or without an FSD hardware enablement/cost, but they all have FSD hardware inside them, and the cost is just about turning it on or not, and you can always later opt to pay the cost or a subscription to enable it. For cars that do have FSD hardware both installed + enabled (paid-for): if you're part of a smaller select group of opt-in, approved testers (currently ~100K drivers in the US plus a smaller number in Canada), you can enable "FSD Beta", which is a whole different animal than Autopilot and not really relevant to the discussion. However, when you're using regular Autopilot, the capabilities of Autopilot are different for cars which have installed+enabled FSD hardware, and those which do not (either because you have the hardware but didn't pay the enabling cost, or because your car is old enough that some of them didn't come with the hardware at all if you didn't pay the cost up front or pay to have it retrofitted). Non-FSD-capability cars, for example, can't detect stoplights on Autopilot at present, while FSD-enabled cars running Autopilot can. There are probably some other differentiators like that as well. Basically, Autopilot-on-FSD-capable-cars is slowly getting minor Autopilot feature upgrades that are only possible with that hardware while they're waiting for the "real" FSD to arrive. Autopilot-on-non-FSD-capable-cars doesn't get these upgrades and is stuck with a more-limited functionality.