Thomas Edison was a serial entrepreneur. He invented a lot of products that became widely used, turned into household names, and changed our lives. He is best known for inventing the light bulb and the phonograph, the former changing drastically how we work and live, and the latter having a tremendous impact on the entertainment industry. Or better yet, creating the entertainment industry. Of course all great inventors usually have a few failures under their belt, in addition to their great successes. One of those failures was ore-milling. But Edison was an entrepreneur.