Good summary!
One slight complication with forex, since it's traded in pairs.
If I'm going long (buying since I think it will go up) on the EURUSD, that means I'm simultaneously long on the Euro and short on the dollar.
If I'm bullish on the dollar (think it will go up) and want to be long on the dollar against the Euro, I'd need to short the EURUSD (sell the pair) since I think the Euro will fall against the dollar.