9. Electricity
- Main People Involved: Thomas Edison, Nikola Tesla/George Westinghouse
Thomas Edison was already a notable inventor before he’d jump into the world of electricity. In fact, we now credit him with several inventions like the Phonograph and even improving the telephone. However, upon moving into electricity he was the leader in the world of Direct Current. This was one of the biggest scientific breakthroughs in history and by the early 1900s, it was used all over.

However, DC used up a lot of power and could only flow in one direction. This forced a need to have power plants relatively close. In an interesting note, Edison hired Nikola Tesla who was tasked with fixing these ailing power stations. Yet he had a better idea for electricity in the form of an Alternating Current, which took less power to operate and flowed both ways. He’d leave Edison behind and partner with the wealthy George Westinghouse to bring AC to the world. AC is now the form of electricity most of us use daily.