The numbers to the left of the decimal point are dollars, and the numbers to right of decimal point point are cents. Here, points are the same as cents. Silver is more like the grains such as corn or wheat. In the paper, you often see it quoted as 599.5, with a change of -5.5. Silver options, however, do trade in one tenth increments, so you can be very precise in buying a silver option.
Copper is quoted in cents per pound, instead of cents per ounce.
A price of 14.50 is fourteen dollars and fifty cents per barrel. Each contract has 1000 barrels, so a price movement from 14.50 to 14.51 is worth ten bucks per contract. Heating Oil and Unleaded Gas are quoted in cents per gallon, just like at the gas pump. Natural Gas is quoted in BTU's, or British Thermal Units, which is a measurement of heat. Cotton is quoted in cents per pound, with 50,000 pounds in a contract.