Who developed the system of electricity we use today? The answer to that question is not who you think it is. My first thought would have been Thomas Edison which is wrong.
The correct answer is Nikola Tesla. He is the person who developed the use of alternating current. Edison, who most of us consider the bearer of electricity, was an advocate of direct current which isn't as efficient. Tesla invited a polyphase alternating current system of generators, motors and transformers. He also help 40 basic US patents on the system. George Westinghouse bought his system from him to supply America with electricity. In 1882, Tesla also discovered a rotating magnetic field which is a key principle in physics. He also devised the first hydroelectric power plant in 1895 at Niagara Falls.