Am i completely wrong though, or just partially???
To explain terms in another Language than the mother language is always difficult, but i want to try it
First:
Every contract has an underlying. Punktum!
The underlying could be an index, an equity, bond, commodity whatever. Usually traders are primary interested in the cash market. They have access to realtime quotes, times and sales etc. so it is much easier to compare.
You can trade these underlyings directly (stock or commodity exchange) or OFF exchange (OTC) with several brokerage companies.
If you are interested in trading leverage products you have to use FSB, CFD, Options or Futures.
With FSB (also with CFDs) you have the opportunity to invest a small amount of money to participate in movements of your prefered underlying.
FSB = Invest a Stake per Point/ Tick/ Pip
CFS = Size
FSB
Stake: 1 € per point = You win/ lose 1 € per Point of the movement of the underlying, Stake 5 per Point = You win/ lose 5 € per Point of the movement of the underlying,
CFD:
Margin 20 %
Size: For 1 Point you leverage with factor 5
Difference between Cash and Future:
Cash like said is always the traded underlying/ or calculated index
The future is also a contract, but instead of a stock exchange it will be traded on a futures exchange. The price is a result of all buy and sell orders in a certain underlying instrument, usually futures. The futures have other characteristics/ specs like regular contracts.
For trading purpose the future market could be/ will be used as indication in which direction the underlying will move.
If you have access to future prices you can compare cash and future. If the future goes down, the cash will follow etc. (its a bit more different in reality)
Here a little more to read from wikipedia
Futures contract - Wikipedia, the free encyclopedia
Future prices you can get (15 minutes delay) directly from the Eurex - THE marketplace for those products
Eurex - Europe's Global Financial Marketplace