McLuhan developed four laws of media that seek to explain the impact of emerging technologies on society and other technologies (Thornburg, 2008). According to Marshall, every technology moves along four stages: enhancement, obsolescence, retrieval, and reversal. The four questions addressed by each are: 1. What does the technology do that is new? 2. What technology does it obsolete? 3. What does it rekindle from the past? and 4. What does it change into in the near future? The following illustrates the four elements of the document camera: Enhancement What does the technology do that is new? Turns text and objects into digital format. Teacher can visually project objects and text for students to see with ease. Obsolescence What technology does it obsolete? This technology makes the overhead projector obsolete. Retrie...