Are there any limits to this though?
Imagine you have 0.01 btc, can you play with 100x and thus trade using 1 btc?
Also I don't get exactly the short and long positions.
When you use leverage, are you still using the regular buy or sell BTC? Then later either sell it high or buy it back low?
Thanks a lot.
No limitations other than exchange ones put on you. Yes you can trade for 1 BTC value using 0.01 BTC, but your range is vastly reduced and is tiny (getting stomped out is easy @100x).
Short=Selling a position
Long=Buying a position
When you go short you are buying the contracts at that price in hopes of selling it later for less, and long is the opposite. You always need buyers on the other side of the contract to take your action, hope that clarifies things.