Nikola Tesla and George Westinghouse power the World's Columbian Exposition 

The International Exposition was held in a building which was devoted to electrical exhibits. General Electric Company (backed by Thomas Edison and J.P. Morgan) had proposed to power the electric exhibits with direct current originally at the cost of US$1.8 million. After this was initially rejected as exorbitant, General Electric re-bid their costs at $554,000. However, Westinghouse, armed with Nikola Tesla's alternating current system, proposed to illuminate the Columbian Exposition in Chicago for $399,000, and Westinghouse won the bid. It was a historical moment and the beginning of a revolution, as Nikola Tesla and George Westinghouse introduced the public to electrical power by illuminating the exposition. All the exhibits were from commercial enterprises. Thomas Edison, Brush, Western Electric, and Westinghouse had exhibits. The public observed firsthand the qualities and abilities of alternating current power.

World's Fair Tesla alternating current presentation
Tesla's high-frequency high-voltage lighting produced more efficient light with quantitatively less heat. A two-phase induction motor was driven by current from the main generators to power the system. Edison tried to prevent the use of his light bulbs in Tesla's works. General Electric banned the use of Edison's lamps in Westinghouse's plan in retaliation for losing the bid. Westinghouse's company quickly designed a double-stopper lightbulb (sidestepping Edison's patents) and was able to light the fair. The Westinghouse lightbulb was invented by Reginald Fessenden, later to be the first person to transmit voice by radio. Fessenden replaced Edison's delicate platinum lead-in wires with an iron-nickel alloy, thus greatly reducing the cost and increasing the life of the lamp.
The Westinghouse Company displayed several polyphase systems. The exhibits included a switchboard, polyphase generators, step-up transformers, transmission line, step-down transformers, commercial size induction motors and...