Craig attempts to explain what augmented reality is as a concept, and what this mean in terms of technology. He describes augmented reality as a medium, and argues that in the same way you would listen to music or watch a film, you experience augmented reality, since it appeals to many senses. Because of augmented realities interactive nature, Craig states that it must be engaged with to truly get this experience out of its application (as opposed to the more passive forms of simply listening or watching a media text). He defines augmented reality as digital information added to the world you exist in, which you can then interact with in the same way you would interact with the real world, as well as any added interaction aided by the technology.
He comments that developments in media and entertainment technology have altered the ‘appetites’ of media consumers, particularly the invention of 3D graphics, and more recently, 3D movies and surround sound systems, paving the way for AR.
According to Craig, the three core components of AR include: sensors (gather input), processors , display. These must all work together to make the digital information fit with the conditions of the real world so that it is sensed as real by the participant. Sensors are particularly important in this process, things such as cameras (using ‘landmarks’ such as fiducial markers) or GPS being used to map the exisiting conditions of the world so that the digital information can be overlaid. He goes on to explain the technology involved, the different applications of AR, and the more technical aspects of processing and displaying information, giving a thorough overview of AR technology and conceptual understanding. Of course, this was published in 2013, so its interesting to consider still how technology has developed since to accomodate AR and how far this varies from what Craig describes.