All terms
The live list of buy and sell orders waiting to be matched.
An order book shows every resting bid and ask at each price. Bids sit below the current price, asks above it, and the gap between the best of each is the spread.
Centralized exchanges have always worked this way. Onchain, order books were impractical until chains got fast enough, which is why AMMs dominated first.
Reading depth on the book tells you where large buyers and sellers are waiting, which often marks where price stalls.
That a wall of orders shows real demand. Orders can be canceled instantly and often are, and placing large orders you never intend to fill is a well known tactic. What has traded is evidence; what is resting is a claim.
Common questions
Why does a DEX not have an order book?
Can I trust what the order book shows?
Where this comes up on the site
The guides that actually use this word, rather than a list of everything we have written.
Where to go next
More trading terms
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