Order flow is the stream of buy and sell orders arriving at a market at any moment, and order flow analysis is the study of that stream — who is transacting, in what size, and with what urgency. In forex there is no single central exchange, so each bank, broker and electronic venue sees only its own slice of the flow and participants infer wider pressure from the prices and volumes they can observe.
Persistent buying interest lifts the offers resting in the book and pushes quotes higher; heavy selling drains the bids and pushes them lower. Because flow reflects completed transactions rather than opinions, it is treated as one of the main channels through which new information reaches price.
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Order Types and Slippage Explained
Market, limit and stop orders trade price certainty against execution certainty — plus what slippage is, where it comes from, and what a stop-loss caps.