Forex Trading Brokers Uk

Forex Questions – Defining various terms?
What are Swap Fees, and how are they calculated?
How is the Margin level calculated, and when will they automatically close losing trades?
Is there any kind of exchange rate with brokers in another country? For example, if I am trading a Demo Account with Alpari UK and I reside in the United States, will some of my profits be lost through any kind of conversion through their domestic currency (the pound)? Or, if I invest in say the EUR/USD, will any of my profits be lost through any kind of conversions from the EUR to the USD?
Thanks in advance.
http://www.forex.com/forex_glossary.html
http://www.babypips.com/forexpedia/
http://forexadvisor.us/
http://en.wikipedia.org/wiki/Foreign_exchange_market
http://glossary.reuters.com/index.php?title=Main_Page
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