Autopilot allows Model S to steer within a lane, change lanes with the simple tap of a turn signal, and manage speed by using active, traffic-aware cruise control. Digital control of motors, brakes, and steering helps avoid collisions from the front and sides, as well as preventing the car from wandering off the road. Model S can also scan for a parking space, alert you when one is available, and parallel park on command.
The Autopilot is learning fast: Model S owners are already reporting that Tesla’s Autopilot is self-improving | Electrek
"During the press conference for the release of the Autopilot, Tesla CEO Elon Musk referred to each Model S owners as an “expert trainer” – meaning that each driver will train the autonomous features of the system to feed the collective network intelligence of the fleet by simply driving the electric vehicle on Autopilot.
He said that the system should improve every day, but that improvements might only become noticeable every week or so by adding up. Just a few weeks after the release, Model S owners are already taking to the Tesla Motors Club forum to describe how the Autopilot is improving…"