Google cars driving two million miles

The self-propelled cars where Google with test since the beginning traveled 2 million miles in 2009 on public roads, or 3.

Google's parent company Alphabet announced this Wednesday. ' You have to understand what's on the road and on the side of the road. Every ride is different, '' said Dmitri Dolgov Google after a ride with Reuters.

The hardest part is learning to predict where for example you have a child going or what another driver. Their decisions are sometimes unpredictable. ' You lost 10 percent of your time to make 90 percent autonomous system. And then you have 90 percent of your time on the last 10 percent, '' said Dolgov.