History has many examples of great innovators who had difficult time convincing their contemporaries of new technology. Even incumbent and powerful companies regarded new technologies as inferior and dismissed it as "toys". Then when disruptive technologies take off they often are overhyped and can cause bubbles like the Internet bubble of the late 1990s. In this lecture we look at some examples of disruptive technologies and the impact they had. We look at the The Disruptive Innovation Theory by Harvard Professor Clayton Christensen.