Blame the media. Blame Google search. Blame lazy marketing. But just like hoverboards that don't actually hover, everything you view in Google Cardboard or Samsung Gear VR or any number of other VR headsets is not necessarily "virtual reality."
But, it's too late to go back now. VR is the catch-all name for all manner of things experienced with goggles on -- from first-person video games that envelope you in a completely computer-generated 3D world to viewing your friend's 360-degree vacation video on YouTube to CNET's immersive CES 2016 coverage.
Of course, there is no real harm done by calling all of the stuff you view in a headset VR. But VR isn't necessarily synonymous with "360 video" -- those "you are there" travelogues that you can access on Google Cardboard and YouTube -- which isn't the same as augmented reality (AR). Meanwhile: Smart glasses and Google Glass? They're something a bit different still. And all of that may or may not have something to do with telepresence (or just "presence"). So for clarity's sake, here's a rundown of everything you need to know about what's what in the world of virtual reality.
What VR is
With the explosion of new devices and content, it might feel like virtual reality is something very new. (A similar thing happened with 3D a few years back.) However, VR, at least in its modern made-for-consumers state, has been around since the '90s. It's just that now the technology has finally caught up with the goal: to transport you into another world that can be experienced and interacted with through the use of sensory devices.
Now, these virtual realities could look and feel like the real world, such as a flight simulator, or be completely artificial like an imagined distant planet, but in any case they're computer generated. Right now, for you and me at least, these other worlds are all about gaming, driven by the likes of the Oculus Rift, Sony PlayStation VR, Samsung Gear VR and HTC Vive (demonstrated in the GIF above).
Through the use of VR headsets loaded with sensors that track your head and eye movements, you're able to interact with and navigate through different environments as if you were actually in them. This is the main thing that separates VR from immersive multimedia content where you're more of a spectator than a participant.
What VR isn't really
The New York Times' NYT VR videos for viewing with Google Cardboard are really cool, but they're not VR. Looking at photos on Flickr VR is really cool; also not VR. GoPro's Surf, Moto and Ski VR videos: same thing.
These are 360-degree videos and photos that capture the entire scene around the camera -- whether it's shot on professional equipment or a $350 point-and-shoot camera. When played back in a VR headset, it can feel immersive -- but what you see is real footage, not a simulation. You can look around and even feel like you're exploring the scenery, but you can't interact with it much and you can't travel within it. You're limited to what cameras can record. It's a new form of photography and filmmaking, but you can watch most of these videos and photos on a regular flat 2D screen, too. 360 degree video is not the same thing as VR.
But the thing is, for most of us, 360-degree spherical content will be the first immersive "VR" experience we have. There is plenty of it already available, and the amount grows daily on YouTube and Facebook. I bet most people who have experienced "VR" on a phone so far are talking about a 360-degree video they've seen, not a game. The amount of 360 video will continue to grow exponentially, too, made by professionals with high-end rigs as well as one of the many cameras coming this year for consumers. It also doesn't require a new computer to enjoy.
To be clear, 360 video can be cool, and even transformative. And it can be transmitted live: we've already experienced presidential debates, pro basketball games, press conferences and boxing matches in VR -- some more successful than others.
Virtual reality and 360 video both have a common factor: Like a good movie, both of them totally transport you to someplace else, be it computer generated or a real-life remote location. Augmented reality, on the other hand, blends your real-world environment with virtual objects that are perfectly inserted into your field of view.
The best example of this right now is Microsoft's HoloLens system. The headset includes a camera, so you see the room around you -- but inside the goggles, you're also seeing giant spiders crashing through the wall. Or it could be something a lot more mundane, but more useful. For example, CNET Senior Editor Sean Hollister experienced what could be the future of car buying as he sat in a showroom and a virtual Volvo S90 materialized in front of him to explore inside and out.
Microsoft isn't the only company working on AR. Another big contender is Magic Leap. While the company's hardware has yet to be seen in public, the stealthy Google-backed startup has released a few snippets of what it says is real-time demos, which little computer-generated robots peeking behind real-world office desks, and solar system models suspended in the middle of a room.
Whether it's Microsoft, Magic Leap or as-yet-unknown developers, though, it's this combination of the real world around you and computer-generated objects that sets AR apart from VR. Basically, it's the difference between creating your own 3D Minecraft world on your dining room table or transporting yourself into that Minecraft world.
OK, so far we have VR that transports you into a computer-generated world and AR that keeps you grounded in your current, real environment. Telepresence sort of twists both together by transporting you into an alternate, real-world environment. Think of it as a video conference call where you can continue the conversation as you walk -- or roll -- down the hall after the meeting ends.
As creepy as it may be talking to an iPad on a stick with two wheels, telepresence robots like the Double, pictured above, allow someone to actually be in an office while working remotely. The Web-connected robots are controlled via a mobile or browser app so you can be in an important meeting even if you're on the other side of the world from where it's physically taking place and actually turn to look at people as if your physical self were present.
Smartglasses and mobile head-up displays
So what the hell is Google Glass, anyway? You might remember Google's 2013 eyewear experiment, and think, "Oh, right. More augmented reality." But that's not quite it. Glass was, instead, just a snap-on head-up display (HUD). It's basically a shrunken down version of what you'd see in fighter jets and some cars, with data and mapping info projected onto the windshield or transparent display. But in the case of Glass, it's a tiny display above the right eye.
The confusion comes in because of the many demo videos Google (and others) released which purported to show first-person views of the Glass experience. In fact, the product did not produce an AR-style overlay to the real world -- it just allowed quick transitions between your viewpoint and your screen. In reality, Google Glass was more like taping an Apple Watch to the side of your glasses.
If that doesn't sound super-exciting for your everyday life, that's probably why Glass never really became a commercial product. But if it sounds useful in niche environments -- grabbing snippets of info without having to take your eyes off the issue at hand -- that's also why Glass is said to be living on with industrial applications. Think surgery, construction, aviation, and the like.
Google Glass seemingly kicked off a whole crop of smart glasses such as the Carl Zeiss Smart Optics above, but as CNET Senior Editor Scott Stein points out, there still isn't a killer app for them yet for consumers and there isn't a good-looking pair to be found.
Personal viewers and virtual screens
Products like the Avegant Glyph may look like a VR headset, but they are more or less a high-tech way to watch movies or other video content. The category isn't new, either: Devices such as the Sony HMZ-T1 Personal 3D Viewer and Zeiss Cinemizer OLED date back to 2012.
The Glyph can be plugged into any thing with an HDMI output, either directly or via an adapter (such as Lightning connector to HDMI). It can handle 3D playback of side-by-side video content, and it does have head-mounted tracking for 360-degree videos, games, and controlling things like DJI drones. But, for now, the available content to take advantage of its full functionality is limited.
As VR and AR mature and real-world spherical video is able to blend more into virtual worlds, we're likely to see splintering into even more categories and uses. But, yeah, except for nerds fighting it out in the comments sections of the Internet, chances are we'll still be calling it all "virtual reality."
Editors' note: This story has been published previously under a different headline. It is otherwise unchanged.