Short answers, pulled from the story.
The War of the Currents began in the 1880s with Thomas Edison's low-voltage direct current system established in 1882 and George Westinghouse's high-voltage alternating current system introduced in 1886. Edison's company supplied 110 volts within a mile of the generating plant while Westinghouse's transformers allowed transmission up to 7 miles in radius.
Harold Brown collaborated with Thomas Edison starting in late 1887 to conduct experiments proving alternating current was more dangerous than direct current. He used Edison's West Orange laboratory to kill dogs and calves with alternating current to influence New York State politicians to adopt the electric chair for capital punishment.
John Feeks was a lineman who died on the 11th of October 1889 after grabbing a shorted high-voltage alternating current line while working in Manhattan. His body fell into the tangle of wires and sparked for an hour, causing public panic that led to legislation requiring utility lines to be moved underground.
The War of the Currents ended with a financial merger announced on the 15th of April 1892 that formed General Electric from Edison General Electric and Thomson-Houston. This merger consolidated the industry into two dominant players, General Electric and Westinghouse, controlling three quarters of the US electrical business.
New York City's Consolidated Edison shut down its last direct-current distribution on the 14th of November 2007 after eliminating service for 4,600 customers in 1998. Broadway theaters continued using direct current until 1975 when computerized lighting control replaced manual resistance dimmer boards.
The Niagara Falls project demonstrated that alternating current could be transmitted over long distances with minimal power loss, making it the superior choice for future electrical infrastructure. Westinghouse won the bid to build an AC power station there in 1892 after underbidding General Electric on the World's Columbian Exposition contract.