™On a quote of $49.95 bid and $50.05 ask, order book helps explain part of what can happen between submitting an order and receiving a fill.
Orders & Market Structure
Order book
A collection of available buy and sell orders at different prices.
Plain-English context
Why it matters
Market-structure language affects how an instruction reaches the market and the price or execution a trader may actually receive.
Assuming Order book has one universal interpretation without checking the source, rules, timeframe or methodology.
Use current definitions. Product terms, tax treatment and market rules can change. Confirm important details with official disclosures, regulators and regulated providers.