Order flow is the sequence of trading instructions and executions entering a market. Depending on the context, analysis may focus on completed trades, changes to resting orders, or both, rather than only the resulting price candles.
Trades and book changes
A trade feed reports executions, while an order-book feed can show orders being added, changed or removed. Removing an offer does not necessarily mean it traded: cancellation can also reduce displayed liquidity.
In trade analysis, buying or selling pressure often refers to the aggressive side that consumes available liquidity. Every completed trade still has both a buyer and a seller. A buy-initiated trade means the buyer acted against a resting sell order, not that the trade had no seller.
Reading the available evidence
Analysts may compare aggressive buying with selling or watch whether resting liquidity replenishes after fills. Feed conventions matter: a reported side can identify the maker rather than the aggressor, depending on the source.
One venue’s flow does not capture the whole market. Hidden quantities, missing messages and delayed updates can limit interpretation. Order flow can describe immediate activity, but it cannot prove every trader’s identity, intention or next action.