How did the 2007 Urban Challenge differ from the two earlier DARPA Grand Challenges? And how did that set the stage for where autonomous cars would go next?Learn more about advertising on the HowStuffWorks podcasts at www.howstuffworks.com/advertisers.htmAnd to learn about your ad choices when listening to podcasts, visit https://www.howstuffworks.com/privacy.htm#ad-choices
