today that industries have become aware of the various kinds 
of business in which they are engaged. When IBM discovered 
that it was not in the business of making office equipment or 
business machines, but that it was in the business of 
processing information, then it began to navigate with clear 
vision. The General Electric Company makes a considerable 
portion of its profits from electric light bulbs and lighting 
systems. It has not yet discovered that, quite as much as 
AT&T, it is in the business of moving information.

     The electric light escapes attention as a communication 
medium just because it has no “content.” And this makes it an 
invaluable instance of how people fail to study media at all. For 
it is not till the electric light is used to spell out some brand 
name that it is noticed as a medium. Then it is not the light but 
the “content” (or what is really another medium) that is