Google Glass developed by Google is a head mounted display that shows information by overlaying on the reality field. Augmented reality is not new, but Google Glass shines with simple and elegant design. Google demoed it at Google I/O conference last year and Sergey Brin wore it before.
Google Glass also responds to voice commands issued by the wearer, you could ask it to grab a picture or take a video and it obeys. Google Glass can be attached with the normal glasses, although these models are not yet available. In future Google Glass might also work with prescription glasses.
If you are wondering how it works to display information and obeys voice commands through voice-augmented display there is an infographic explaining the inner workings of Google Glass. It has a CPU, camera for photo, video, GPS etc. It has a mini projector which projects a layer via a semi-transparent prism directly on the retina in the eye. Depending on how you wore the Glass the layer appears in the middle or in the corner. See the infographic to see how it works. This Infographic is created by Martin Missfeldt