Exchanges:

CME - Currency and Live Cattle

Cattle - 40,000 pounds expiring 2, 4, 6, 8, 10, 12th month
Hogs - 40,000 pounds expiring 2, 4, 6, 7, 8, 10, 12th month

CBT - Wheat, Corn, Soybeans, US. Treasury

Wheat - 5,000 bushels expiring 3, 5, 7, 9, 12th month
Soybeans - 5,000 bushels expiring 1, 3, 5, 7, 11th month
Corn - 5,000 bushels expiring 3, 5, 7, 9, 12th month

NYBOT - Coffee, Sugar, Cotton

Coffee - 37,500 lbs expiring 3, 5, 7, 9, 12th month
Sugar - 112,000 lbs expiring 3, 5, 7, 10th month
Cotton - 50,000 lbs expiring 3, 5, 7, 12th month

NYMEX - Oil and Natural Gas

Crude Oil - 1,000 barrels expiring all 12 months
Heating oil and Gas - 42,000 gallons expiring all 12 months
Platinum and Palladium

COMEX - Precious Metal

Gold - 100 troy ounces expiring 2, 4, 6, 8, 12th months
Silver - 1,000 troy ounces expiring 3, 5, 7, 9, 12th months
Copper - 25,000 lbs expiring 3, 5, 7, 9 12th months
Aluminum and Zinc - 25 metric tons expiring all 12 months

Futures price = spot price + cost of carry (how much it costs to have counterparty holding the commodity till expiration)

Contango - Futures price higher than spot price, typically found in non-perishable commodities with a low cost of carry.

Backwardation - Futures price lower than spot price, when a premium is placed on having the commodity in inventory offsetting the cost of carry. That can happen when there is a high probability of supple disruption.

Backwardation also occurs when hedgers of a commodity selling the futures overwhelm speculators buying the futures, which signals a bearish view of the commodity