For some reason the Rift gets compared with Google Glass, but aside from the fact that they are both pieces of technology that you wear on your face, the two devices are entirely different animals. Google Glass is a tiny smartphone in the shape of eyeglasses with a clear rectangular see-through screen over one eye. You can see your real surroundings at all times, but you can also call up information via voice commands, and it will appear on the screen, superimposed over what's really in front of you. It's more in the realm of augmented reality than virtual reality.
The Oculus Rift, on the other hand, is true virtual reality. You are completely blocking your view of the real world and seeing a new digital, virtual world in its place. The Rift uses stereoscopic 3-D rendering, a high-resolution display, a field of view 110 degrees wide and ultra-low latency head tracking to immerse you in a virtual world that should prove to be more believable than any VR most of us have witnessed before.
The Rift achieves stereoscopic 3-D by feeding a slightly different image to each eye, which is more or less how we see in 3-D in the real world, where each eye is seeing everything from a slightly different vantage point and the differences are used to perceive depth. The110-degree field of view extends into your peripheral vision area and, in conjunction with the lenses, is intended to help immerse you into a game. The low latency means that what you see tracks with your head movements in real-time rather than being on a delay where the image has to catch up to your eyes.
Once you've acquired the developer's Rift and downloaded the SDK and any firmware updates from the Oculus VR site, you need to calibrate the device. This includes measuring and setting your height and your IPD (interpupillary distance, or the distance between your pupils) and running the magnetometer calibration, which involves rotating the headset as instructed. Once your device is calibrated, you can use it to test or play whatever games you find or create.