We're right on the edge of dual revolutions in artificial reality and augmented reality. It's an exciting time because we're in the final days of a world in which these technologies are considered "futuristic." By next year, early adopters will have them in their homes. Within three years they'll be mainstream.

But I've buried the lead. The real story is that virtual reality and augmented reality are practically the same thing and will be served up to us in breathtaking and unexpected ways.

What's the difference?

Both augmented and virtual reality involve computer-generated objects, people and text, which appear real or almost real to the person experiencing them. The difference is in the environment. In virtual reality, the environment is also computer-generated, whereas in augmented reality, the environment is real life.

In the 1980s, when the virtual reality concept first came into the popular imagination, it was something like the Holodeck first introduced to viewers on the TV series Star Trek: The Next Generation in September 1987. In that vision, virtual reality was a complete -- and completely convincing -- alternate reality indistinguishable from the real thing.

Popular culture got its first mainstream look at augmented reality in The Terminator. In that movie, the robot played by Arnold Schwarzenegger looked at real-world objects and received data about them, along with options for actions to take, scrolled into the periphery of vision.

In the one case, virtual reality replaced reality. In the other, reality was annotated. But now that the technologies have evolved to the brink of mainstream usage, it turns out that these early visions barely resemble the realities we're about to have access to.

Let me give you some real-life examples.

Magic Leap

A secretive startup called Magic Leap was in the news this week because Google is leading a $500 million round of investment in the 100-person, Florida-based company.

Not much is known about Magic Leap's technology, other than the fact that extremely knowledgeable people who have experienced their demo have come away astounded.

Apparently the company can create convincing, high-resolution 3D images that appear to be in the physical space right in front of you.

This basic idea fits neither the virtual reality nor the augmented reality paradigms. The environment isn't simulated. And reality isn't augmented. (It doesn't identify a real elephant and tell you about it; it creates the illusion of an elephant that isn't really there).

The company has trademarked its own label for the technology: Cinematic Reality.

Project Tango

Placing virtual objects in real spaces and having them interact with real objects requires a computer understanding of where all the walls and floors and ceilings and surfaces are.

Google is working on a combination hardware-software technology to be built into smartphones and tablets that maps physical reality in real time. The research initiative is called Project Tango.

Once a room is mapped, one application is virtual reality like simulations and games, but with the real world as the environment. For example, when you look at the screen of a phone or tablet, it might appear as though virtual-reality balls were bouncing down the stairs, and chairs and couches protect gamers from simulated laser beam weapons.

The way to look at Project Tango is that it creates an invisible virtual reality environment out of the real world environment, so the virtual objects interact with the constructed reality while the user still sees the actual reality.

Oculus Adding a Leap Motion gesture device to Oculus VR's virtual reality headset brings the user's hands into the virtual environment.

Oculus Rift + Leap Motion

The leading brand, if you will, in the coming consumer virtual reality space is Facebook's Oculus Rift platform. It's available only to developers and other ecosystem builders.

Oculus by itself is straight up old-school virtual reality. But a special project with Leap Motion -- a high-fidelity, in-the-air gestures product already on the market -- adds reality to Oculus. By bolting a Leap Motion device to the front of an Oculus Rift headset, and mapping hand gestures into to a virtual reality scene, users can see their own hands in the virtual space (of course -- software can make them gorilla hands, robot hands -- you name it), and those hands can manipulate 3D virtual objects in the simulation.

This is the Project Tango idea inside out. Instead of the real world being duplicated to create a hybrid real-virtual environment, the environment is fully simulated but the user is duplicated -- or, at least parts of the user.

Microsoft IllumiRoom

Microsoft Research is working on a patented technology that uses projectors to display game play onto the walls, ceiling and floor of a room.

The basic application is that you play some future Xbox game. As is the case today, the main game play happens on a TV screen. Let's say you're playing a first-person shooter in a tropical jungle. IllumiRoom would project the rest of the jungle all over the room -- creating peripheral vision to the focused play on screen.

This again challenges the notion of virtual reality. The room is real, but the jungle is virtual and computer-generated.

Microsoft Microsoft is working on creating a virtual environment by projecting it on the surfaces of a real room.

Casual virtual and augmented reality

The biggest disruption to our long-held expectations about the future of virtual and augmented reality is the casualness with which we'll use it.

All prior visions involved super complicated and expensive hardware. But as of this summer, it's becoming clear that virtual interfaces will be available to the masses at very low cost and with very little difficulty. In fact, they will become something of a banality.

Google casually distributed examples from a project called Cardboard to attendees of its Google I/O conference in the summer. The handout was a pair of cardboard virtual and augmented reality goggles to be assembled by the user. Then, after downloading a free app, the user's smartphone could be inserted into the cardboard headset, creating convincing virtual reality that used the phone's screen, motion sensors, speakers and other features -- including, potentially, the camera for augmented reality or some combination of virtual and augmented reality.

Because Cardboard is an open-source project, many other companies have offered kits for sale at a variety of prices starting at $6.99.

The core idea behind Cardboard is the use of the smartphone you already own as the screen, computer, speaker and sensors of the virtual or augmented reality experience. Note that smartphones have a screen on the front and a camera on the back, which is perfect for virtual reality, augmented reality or a mashup of the two. It just depends on the software.

Since Google's handout, other companies have announced goggles based on the same concept. New entrants include Samsung, Archos and even camera lens maker Carl Zeiss, at various levels of sophistication, power and price.

Everybody's talking about virtual reality and augmented reality, both of which are on the brink of going mainstream.

But the real story is the incredible blurring of the lines between the two, and the many mashups and variations and options that are in the works.

Ultimately, virtual reality and augmented reality are the same thing, or nearly so. They're about to become available, to all of us, and it's going to be far cooler than we ever imagined.