# What a robotaxi service is

Lesson 1 of [Robotaxi foundations for riders](https://robotaxis.fyi/academy/robotaxi-foundations.md), 12 minutes.

A robotaxi service is a ride service where software drives the car. On this site, one listing is one operator running rides in one city. Waymo in Phoenix is one listing. Waymo in San Francisco is another.

## The automation levels

SAE J3016 is the common reference for the words used about driving automation. It defines six levels, from 0 to 5.

- **Levels 0 to 2**: driver support features. A human drives and supervises at all times.
- **Level 3**: the system drives inside its design limits. A human must be ready to take over when the system asks.
- **Level 4**: the system drives and handles a failure by itself inside its design limits. No one in the car needs to take over.
- **Level 5**: the same as Level 4, with no limits on where or when the system can drive.

The levels describe a driving automation feature, not a brand. J3016 is a technical classification. It is not a law and it does not rate safety.

## The operational design domain

J3016 calls the conditions that a system is designed to work in its operational design domain (ODD). An ODD can limit the place, the road type, the time of day and the weather. The service area on a listing is the place limit that you can see on a map. Other limits can apply too.

## Words to use with care

J3016 advises against the word autonomous for these systems. It uses driving automation instead. Many operators and regulators still say autonomous, so you will see both words.

## Sources

- SAE J3016, Taxonomy and Definitions for Terms Related to Driving Automation Systems for On-Road Motor Vehicles, revision J3016_202104
- This site, guide What a robotaxi listing shows

Also on the [web page](https://robotaxis.fyi/academy/robotaxi-foundations/what-a-robotaxi-service-is).