Glossary
Market data terms
Short definitions for order-book and prediction-market concepts, plus how AymarData stores and serves each one.
- Binary optionA binary (digital) option pays a fixed payoff if a condition is true at expiry and nothing (or a smaller fixed amount) o…
- DepthDepth describes available liquidity away from the best bid and ask — either as the number of price levels shown or as cu…
- Funding rateA funding rate is a periodic payment between long and short holders of a perpetual futures contract, designed to keep th…
- Implied probabilityImplied probability is the market’s price-implied chance that an event occurs. On binary prediction markets, the mid (or…
- L2 order bookAn L2 (level-2) order book lists aggregated size at each price level on both the bid and ask sides, not just the single …
- Mark priceMark price is an exchange-computed reference price for a perpetual (or futures) contract, often based on an index and ba…
- Mid-priceMid-price (mid) is usually (best bid + best ask) / 2 when both sides exist. It is a simple fair-value proxy that ignores…
- Open interestOpen interest (OI) is the number of open derivative contracts (or notional) that have not been closed or settled. Rising…
- Order book deltaAn order book delta (or diff) updates a single price level: new size, or removal when size goes to zero. Applying deltas…
- Perpetual futuresPerpetual futures (perps) are derivative contracts with no expiration date. Instead of converging at expiry, they use fu…
- Prediction marketA prediction market lets participants trade contracts whose payoff depends on the outcome of a future event — elections,…
- SettlementSettlement is the process that finalizes a contract — paying winners on a prediction market, delivering underlying on a …
- SnapshotA snapshot is a complete view of the order book (or a depth-truncated view) at a moment in time. Snapshots are used to i…
- SpreadThe bid-ask spread is best ask minus best bid. It is a quick measure of transaction cost for crossing the book at the to…
- Tick sizeTick size is the smallest allowed price increment for orders on a market. Books only quote at valid ticks; adjacent leve…
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