Trading leverage or leveraged trading allows you to control much larger amounts in a trade, with a minimal deposit in your account. Leveraged trading is also known as margin trading. You can open up a small account with a brokerage, and then essentially borrow money from the broker to open a large position. This allows traders to magnify the amount of profits earned.
Currencies are traded on the Foreign Exchange market, also known as Forex. This is a decentralized market that spans the globe and is considered the largest by trading volume and the most liquid worldwide. Exchange rates fluctuate continuously due to the ever changing market forces of supply and demand. Forex traders buy a currency pair if they think the exchange rate will rise and sell it if they think the opposite will happen. The Forex market remains open around the world for 24 hours a day with the exception of weekends.