What is the computer highway system?
It seems like the computer highway to which you are referring is the internet highway or information superhighway. These terms refer to the vast collection of resources available to us via our network of computers. Across the world we are connected through internet services, bulletin boards, websites, a great assortment of communication networks like cable, cell phones, fax machines and any other form of electronic communication you can find.
All of these forms of communication and information processing contribute to a "highway" that is complex and large. Just think about the interlocking structure of these systems throughout the world for all of the information we can discover. Like a transportation highway on which we might drive, there are many different paths one can take to go in a different direction. Like in driving, we need to eventually go along the a path to find our destination.