Teslas do not have gears. This means they can accelerate faster and much smoother.
They often can take advantage of Regenerative braking which allows 1 pedal driving since the car will slow rapidly when the throttle is not pushed (this can be disabled in Settings – Driving Regen braking set to low). Teslas are like a jet ski in that they slow down when not in gear since the car can use the brakes to charge the battery.