The basic concept of self-driving cars has been around for a long time. Google’s Waymo and General Motors Cruise have advanced so quickly that legislation on the legality of self-driving cars has struggled to keep up.

The self-driving car industry has been struggling for years, with more and more companies dropping out due to technical issues. There used to be eight companies on this list, but by 2024, only four will be on the list.

Waymo began as a project at Google and operated in relative obscurity and secrecy for a surprisingly long time. By the time Google went public with its self-driving car program and later spun Waymo off as a separate subsidiary of Alphabet Inc., they had already begun.

Waymo's biggest drawback is that it is essentially a technology startup with deep expertise in artificial intelligence (AI) and machine learning, but it is not part of, nor backed by, an automaker.