Financial energy commodity contracts are traded on the New York Mercantile Exchange (NYMEX). The New York Mercantile Exchange building is located on the Hudson River in New York City and owned and operated by CME Group of Chicago (Chicago Mercantile Exchange & Chicago Board of Trade). NYMEX has offices in other cities as well (Boston, Washington, Atlanta, San Francisco, Dubai, London, and Tokyo.) The New York Mercantile Exchange started in the 1800s. There were scattered markets for the goods in large cities. You can picture a city like New York City and agricultural products being brought in and sold in various parts of it. So, some entrepreneurial businessmen decided that they needed a central exchange. So, in 1872, it was founded as the Butter and Cheese Exchange. In 1880, it was changed to the Butter, Cheese, and Egg Exchange. And then, finally, in 1882, it was changed to its present name, the New York Mercantile Exchange.
Later products would include yellow globe onions, apples, potatoes, plywood, and platinum. Platinum is the only one of these products which is still traded today on the New York Mercantile Exchange. Today, it trades crude oil, heating oil, gasoline, propane, natural gas, platinum, and palladium.
For a quick overview of the Exchange, view this "This is NYMEX" video (2:20 minutes).