The idea can be tempting: sit back, relax and let your car do the driving. The seemingly far-fetched concept has penetrated the realm of plausibility thanks largely to tech giant Google, which reports that it has been successfully testing a fleet of autonomous cars for years on public streets.

The self-driving cars are fitted with sensors that detect lanes, stoplights, traffic and other obstacles, and link that information with GPS data. Google and several automakers have retrofitted everyday cars with this technology; Google has reportedly racked up 700,000 miles on a fleet of about a dozen cars.

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Google has sought out legal approval for its tests, which have been legal in Nevada since 2011. California, Florida and Michigan also now allow self-driving cars on the streets, and other states have sometimes offered one-time special permission to carry out demonstrations of the technology. Other testing is taking place legally in other countries.

The rules are strict, though, for the time being. Today’s autonomous cars must have all of the same manual controls as ordinary vehicles and a licensed alert driver who can take over from the computer at any time. Google, though, recently unveiled a car without a steering wheel or brake pedal, and intends to manufacture 200 of them to test.

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There’s a more practical hurdle for most drivers, however, regardless of the technology’s legality: you can’t buy a self-driving car. The only models on the road are in the development stage. But some analysts predict they’ll hit the market by 2020, so expect to see significant debate over whether and how to allow these autonomous vehicles on the street before that happens.

Note that some self-driving technology is available – and legal – on cars today. Radar-based cruise control varies your speed if you come up behind a car that’s going more slowly in front of you, with some systems even able to bring you to a complete stop. Automatic braking systems are becoming increasingly popular, jumping in to prevent or scale down the force of a possible collision. And some cars even pull off automatic hands-free parallel parking.

Brady Holt, a Washington D.C. newspaper reporter, has had a lifelong interest in cars in the automotive world, and he’ll share his thoughts at every available opportunity. Brady has written for since 2008, publishing hundreds of car reviews, automotive news pieces and other features. His work can be found on

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