What examples of technological innovation can you identify? What forces lead to the commercialization of the science behind those technologies? Did the capability exist before the market demand, or was the demand there before the technology was available?

Part I: What examples of technological innovation can you identify? What forces lead to the commercialization of the science behind those technologies? Did the capability exist before the market demand, or was the demand there before the technology was available?
Part II: Why would a company choose to follow rather than lead technological innovations? Give an example of a company that leads and one that follows.