Forex (Foreign Exchange) is the global over-the-counter currency market. Unlike a stock exchange it has no single venue: deals are struck directly between banks, funds, companies and brokers around the world, 24 hours a day from Monday to Friday.

The basic unit of the market is the currency pair. EURUSD = 1.0850 means one euro buys 1.0850 dollars. The first currency in the pair is called the base currency, the second — the quote currency. Buying the pair means buying the base currency with the quote currency; selling is the opposite.

The price is formed by the order flow of the largest participants — market makers and top-tier banks. A broker aggregates these liquidity streams and passes the best prices to clients. The difference between the buy (Ask) and sell (Bid) price is the spread — the main transaction cost for a trader.

The minimum price increment is a pip. For most pairs it's the fourth decimal place: a move in EURUSD from 1.0850 to 1.0851 is one pip. A standard lot equals 100,000 units of the base currency, while modern brokers let you trade from 0.01 lots.

Start with a demo account: it fully replicates live trading with zero risk to your capital. Practice order mechanics, stop losses and position sizing there — and only then move to a live account with an amount you can afford to lose.