Since there is no IC engine, how does Tesla record usage of its vehicles? Is it recorded by time like in a boat/plane, mileage, or number of recharge cycles?
It has an odometer, like most cars.
In addition to that, the battery and the motor controller is stuffed with electronics that log every electrical event (charge + discharge current, voltage, speed, temp, AC on/off, etc.) Some enthusiasts came up with their own hardware + software to plug into the car's diagnostic socket and make available all of that information in a user-friendly way. The data logged by the vehicle is periodically uploaded to Tesla for analysis. They can tell you a quite detailed history of every car (not that they would, of course).
I hope it is held securely. Is the a carfidentiality agreement?
typo: Is there a ...
Tesla isn't going to report you for speeding on public streets. That wouldn't be good for business. I don't know if there's a confidentiality agreement though.
I think there is, for the data they collect from the car.