The concept of "autonomy levels" was originally published by the international Society of Automotive Engineers (SAE) in 2014, as part of its "Taxonomy and Definitions for Terms Related to On-Road Motor Vehicle Automated Driving Systems" report

1. Driver Assistance - Hands on the wheel
   In certain driving modes, the car can either take control of the steering wheel or the pedals. The best examples of level one automation are adaptive cruise control and park assist.
2. Partial Automation - Hands off the wheel, eyes on the road.
   Under certain conditions, and the driver must maintain ultimate control over the vehicle
3. Conditional Automation - Hands off the wheel, eyes off the road Ð sometimes
   Driver is expected to retake control when the system asks for it
4. High Automation - Hands, off, eyes off, mind off Ð sometimes
   It can drive itself full time under the right circumstances, and if it encounters something it can't handle, it can ask for human assistance, but will park itself and put its passengers in no danger if human help isn't forthcoming.
5. Full Automation - Steering wheel is optional.
   The front seats might face backwards to make this a social space

Timeline:
2015 
Baidu, a Chinese internet company, has been publicly testing its self-driving-car technology

An Audi A7 drove 550 miles in autopilot mode from Silicon Valley to Las Vegas.

2016
In April of 2016, Fiat-Chrysler began a partnership with Google and itÕs Waymo project
 to create a fleet of 100 self-driving Pacifica minivans that will be tested this year
  on the streets of Arizona, California and Michigan. 
  
  Tesla's Autopilot system had a fatal accident in May 2016
  It was categorized as driver error because they were misusing Autopilot
  
2017 - Level 2 - Tesla S

Announcements as of June 2017

  Elon Musk predicted a level 4 by the end of 2018
  and a true level 5 Tesla in about 2 years (2019).
  
   FordÕs existing self-driving car efforts with Argo AI plan to have a Òfully autonomous vehicleÓ
    coming in 2021
   
  According to Reuters, GM is rumored to have plans to deploy thousands of self-driving
   electric cars next year (2018) with its ride-sharing affiliate, Lyft
   
   HondaÕs long-stated goal is to have cars with Waymo self-driving technology 
   that can at least drive themselves on highways by 2020.
   
   Toyota company hopes to launch products based on its Highway Teammate programs in 2020
   
   Renault-Nissan: 2020 for autonomous cars in urban conditions, 2025 for truly driverless cars
   
   Volvo: Self-driving on the highway by 2021
   
  Hyundai: Highway by 2020, urban driving by 2030
  
  Daimler: Nearly fully autonomous by early 2020s
  Fiat-Chrysler: CEO expects there to be some self driving vehicles on the road by 2021
  
  BMW: Fully self-driving vehicles possible by 2021
  
  Delphi, an auto electronics supplier, aims to release self-driving vehicles to the public in 2022