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When Google announced a do-it-yourself virtual reality kit made of cardboard at its I/O developer conference this week, one of the first questions people asked was: Is this a big joke?

Was Google mocking VR and poking fun at Oculus, the VR goggle makers Facebook acquired for $2 billion? Or maybe the company was just pulling a gag on attendees, who were excited to get a free smartwatch in their conference goodie bag?

Turns out, Google is using cheap, corrugated paper to give virtual reality its neatest and most accessible tool for converting nonbelievers. While it's no Oculus Rift headset, Google's Cardboard initiative has a huge role to play in VR by putting it in the hands of anyone with $25 and a smartphone.

VR is supposed to change everything: film, gaming, communication, travel, education -- even what we understand about sensory experience itself. Oculus is the once-scrappy outfit started by 21-year-old Palmer Luckey that was purchased by Mark Zuckerberg's social network in March. Oculus, now flush with resources and the game industry's finest minds, is the VR torchbearer, blazing a trail toward a bright future we'd thought only science fiction could provide.

But for most people, consumer VR is still a fringe technology. It's a futurist's fantasy easily caricatured, an activity we could see devolving into the kind of techno-dystopian world that we fear Facebook and the smartphone era has already begun creating. That's a realm where people sit in the living room with computers strapped to their faces, ignoring each other and escaping even further from reality and face-to-face contact.

The crucial disparity between the critical reception of Oculus' product and the public's perception of VR is a problem. It arises from the fact that the technology, as it stands now, is firmly in the "you have to see it to believe it" camp of consumer electronics. Unless you've strapped an Oculus Rift or Sony's Project Morpheus to your face -- devices that quite literally change the world before your eyes -- you're not likely to think a high-fidelity VR headset is really a product category capable of changing industries.

Why? Well, most everyday technology users don't frequent electronics trade shows or game developer conferences, where the Rift and Morpheus are trotted out and where attendees line up to give them a whirl. So while technologists believe in VR, our friends, family, and the folks freaked out by Google Glass, the company's smart eyewear, aren't going to have the opportunity to try out a modern-day VR experience until full-blown headsets arrive in the next year or so.

That's where Google Cardboard, perhaps one of the most important, quirky, and ingenious advances in consumer VR since the Rift itself, comes in.

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Announced as part of Google's annual product giveaway at I/O, Cardboard is a meant to be a super-low-cost, crowdsourced toolkit anyone can build to run elementary VR experiences. Essentially, it's a cardboard housing for a smartphone running Google's Android mobile OS. You get a $10 lens kit, about $7 in off-the-shelf magnets, $3 worth of velcro, a rubber band, and an easily programmable $1.50 Near-Field Communication sticker tag for launching the companion mobile app automatically.

You can even cut the cardboard housing, the schematics for which are posted online (PDF), out of a pizza box.

The result is a low-key yet completely usable headset that's good enough to hand to a stranger and have them experience a genuine VR revelation. In fact, countless people -- at San Francisco's Moscone Center and here, too, at CNET's headquarters -- who have never had the opportunity to try on a Rift have been holding up Cardboard's goofy-looking smartphone mount and walking away thinking VR might not be so crazy after all.

They also say it may just be the coolest tech they've played with in a while.

Google's Cardboard app, which is what plays on the phone screen while it sits in the cardboard casing, lets you cruise through a landscape or city street in Google Earth and watch YouTube videos in a virtual theater. Even wackier Web-based experiences -- what Google is calling Chrome Experiments -- let you play a simple coin-collecting game, visit the Great Barrier Reef in a helicopter, and ride a roller coaster. That only one of the more than a dozen apps you can access with Cardboard is game-related is a boon for VR too, proving that you can design worthwhile and interesting experiences in a first-person view.

Google

Those VR demos are just the beginning. Google released an open software development kit for anyone to download and tinker with. The SDK is experimental -- meaning it won't get the same attention as, say, Google's mobile operating system Android. But it's a good enough start to get developers crafting new and unique ways to use Cardboard, all in a low-cost, crowdsourced environment.

"Developing for VR still requires expensive, specialized hardware," Google writes on its dedicated Cardboard developers page. "Thinking about how to make VR accessible to more people, a group of VR enthusiasts at Google experimented with using a smartphone to drive VR experiences."

"By making it easy and inexpensive to experiment with VR, we hope to encourage developers to build the next generation of immersive digital experiences and make them available to everyone," Google concludes.

Of course, Cardboard is not going to have the graphical fidelity of Oculus' current VR demos. Think of Rift showing you what's it like to jump into the console video game on your big screen, while Cardboard is more like immersing yourself in a not quite grainy, but not exactly crisp image of a smartphone app.

While the Rift headset also uses smartphone screens as its display, the device powers its software from a high-end gaming PC. So don't expect, with Cardboard, to experience anything on the level of Sony's dragon-fighting, archery demo for the Morpheus headset or the dog fighting spacecraft game Eve: Valkyrie that runs on the Rift.

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Oculus has also built out its ranks with some of gaming's most technically gifted minds, from Id Software co-founder and Doom creator John Carmack to Valve's Michael Abrash. Those additions helped the company develop techniques for vastly reducing latency. That means bringing in line the motions of your head with what's on the screen -- as well as cutting down the smearing of images when you move too fast.

To make the experience even closer to reality, the Rift has a camera that works with dozens of infrared sensors to keep track of how you move, letting you crouch and even lean forward and peer sideways by dipping your shoulder down. None of those advancements are built into Google Cardboard, which is powered by your smartphone. So while you can't do anything other than look around using Cardboard, it still may present a problem if you're easily made nauseous at even the slightest motion-inducing activity.

Still, the idea behind Cardboard isn't to undermine the technical achievement and feasibility of professional-grade VR headsets, but rather to close the loop from the bottom up. Now, with Oculus and Cardboard, we have a full spectrum for VR, with both DIY and high-end hardware optimized for apps both large and small, serious and playful.

More than anything, Cardboard illustrates Google doing what it does best: handing everyday people the tools to build the kinds of experiences that larger companies, including itself, would otherwise never consider or have time for. It just so happens that in creating Cardboard, Google has designed the blueprints to a device that can convince the world that VR is mind-blowing, about to arrive, and about way more than just gaming.