CFDs based on Futures Prices are different from those based on Spot Prices (also known as Cash Prices).
Futures prices are based on the price of a derivative contract for delivery of an underlying asset, such as gold, at a specified future date. Whereas the "spot" price is the current price at which a given underlying asset can be bought or sold in the market for cash.
In the case of Futures, they're often used to hedge against the risk of fluctuations in the price of commodities such as Coffee and Cocoa for example, where producers of those commodities may wish to lock in a known price for their product that they are planning to sell at a future date.