Microsoft demonstrates its upcoming HoloLens virtual-reality device by showing a “mixed reality” game that combines animation with real-world objects, during a presentation of new devices, in New York, Tuesday, Oct. 6. Attacking robots know how to break through walls and go around furniture. Developers will be able to buy a prototype early next year for $3,000. Credit: AP Photo/Richard Drew

Which reality do you prefer? That may be an increasingly common entertainment choice in the next year or two as virtual-reality headsets such as Sony’s Project Morpheus and Facebook’s Oculus Rift go on sale and as companies such as Microsoft push augmented or “Mixed”-reality technology with what it’s calling “HoloLens.”

But what’s the difference between these technologies? There’s a lot of crossover, but generally speaking, virtual-reality is more fully immersive. Imagine “Tron,” in which the human characters are inside a virtual world. A headset like Oculus Rift or Samsung’s GearVR could simulate that in a video game, or in films such as the ones at Wednesday’s Kaleidescope VR Film Festival.

Augmented reality or mixed reality is more like a virtual layer on the real world or real-world objects (say a basketball) interacting with virtual settings. A cell phone app that appears to make a virtual, 3-D-animated pet show up on your coffee table would be one example of augmented reality.

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