The words, defined once

Most of the confusion in this market is vocabulary rather than mechanism. Two venues publish a funding rate and pay it on different things; two data vendors both say “historical” and mean a decade apart. Each entry says what the word means here, and what it changes about a purchase.

Builder feealso builder fees, builder code, builder codes: A builder fee is an extra charge Hyperliquid adds to a fill and pays to the software that sent the order, on top of the venue's own trading fee. You sign a maximum for each builder address once; the front end then sets the actual rate order by order, up to that ceiling and a protocol cap of 0.1% on perps and 1% on spot. It is how many free terminals and bots get paid.
Circulating supplyalso circulating market cap, free float supply: The number of a token's units a data vendor judges to be in public hands and tradable, as opposed to minted but held by insiders, locked, bought back or unminted. No chain records it: each vendor derives it from balances and a rulebook of its own, so it is the supply behind a ranked market cap and the figure most likely to differ between two sources quoting the same token.
Cumulative volume deltaalso CVD, volume delta: Cumulative volume delta is a running total of buying volume minus selling volume, where a trade counts as buying when the aggressor, the taker who crossed the spread, was the buyer. Computed from individual trades it is exact for the venues included; computed from candles it is an estimate. Its level depends on where the sum started, so only its changes compare across tools.
Footprint chartalso footprint charts, cluster chart, order-flow footprint: A footprint chart splits each bar into its price levels and prints, at every level, how much traded there by aggressive sellers and how much by aggressive buyers. It cannot be drawn from candles: it needs every trade with its price and aggressor side, so how much footprint history a tool shows is decided by how much trade data it recorded, not by its chart.
Funding ratealso funding, funding rates: A periodic payment between the two sides of a perpetual swap that holds its price near the index. Longs pay shorts when the rate is positive, shorts pay longs when it is negative, and the venue takes no cut. It is quoted per settlement interval, not per year, and the venue picks the interval — eight-hourly is the common convention and several settle hourly, so two quoted rates can be the same word and a different quantity.
Grid botalso grid trading, spot grid, futures grid: A bot that splits a price range into levels, rests buy orders below the current price and sell orders above it, and replaces each filled order with its opposite one level away. Levels are spaced by a fixed amount (arithmetic) or a fixed ratio (geometric). It trades only inside the range, and the profit it reports usually counts completed buy-sell pairs, not the inventory it is still holding.
Implied volatilityalso implied vol, mark IV: The annualised volatility that makes an option pricing model return a price the market actually shows. In crypto it is usually solved from a premium quoted in bitcoin or ether, against a forward rather than spot, on a calendar that never closes. Deribit publishes three per option, from the bid, the ask and its own mark, and accepts orders typed in volatility instead of price.
Liquidationalso forced liquidation: The venue closing a leveraged position because its margin has fallen below the maintenance requirement. On most perpetual venues the trigger is a mark or oracle price rather than the last trade, and the close is sent as orders into the book by the venue's risk engine. Losses beyond the posted margin fall to an insurance fund and, once that cannot absorb them, to profitable traders on the other side through auto-deleveraging.
Mark price: The price a derivatives venue uses to value open positions — for unrealised profit and loss, margin checks and the liquidation trigger — in place of the last traded price. Each venue computes its own, usually from an index of spot prices on other exchanges plus a smoothed basis, so the mark price of a BTC perpetual differs between venues and from the price a chart of trades shows.
OHLCValso candles, OHLC, candlestick data: OHLCV is a bar summarising trading over a fixed interval — open, high, low, close and volume — computed from a venue's trade prints rather than observed directly. Every candle is an aggregation, and the interval boundary, the timezone it aligns to, the trades included and the fields returned are all the publisher's choices. Two feeds labelled one-minute candles for the same pair are routinely different series.
Open interestalso OI: The number of derivative contracts open at a point in time — entered into and not yet closed, expired or settled. It counts positions outstanding rather than turnover, so a trade between two existing holders moves none of it while volume still rises. Every long is matched by a short, so there is one market-wide total and not two. Each venue reports it in units of its own choosing.
Oraclealso price oracle, oracle price: A mechanism that puts an outside price where a contract or a matching engine can read it. On a chain it is a feed such as Chainlink or Pyth, written on-chain on a threshold, a heartbeat or a user's request. On a perpetuals venue it is the venue's own reference price, a median of other exchanges' spot prices. Both are reported values with a timestamp, never a live market.
Perpetual futuresalso perpetual swap, perpetual contract, perps: A futures contract with no expiry date. Nothing forces it to converge on spot at delivery, so a periodic funding payment between longs and shorts pulls its price toward an index instead. Each venue lists its own: a BTC perpetual on two exchanges is two instruments, with separate order books, indices, margin currencies and contract sizes, and the price it trades at is not the spot price.
Rate limitalso rate limits, rate limiting: A rate limit is the ceiling a provider puts on how much of its API you may consume, and the unit it is counted in is the vendor's own choice — requests per second, calls per minute, weighted cost per minute, credits per month, or a counter that decays while you wait. Two limits quoted in different units cannot be compared, and the identity they are charged against differs as well.
Redistributionalso redistribution rights, redistribute: Redistribution is showing market data, or anything derived from it, to somebody outside your own organisation. Vendors licence it separately from the right to use the data internally, usually at a different price and often only by negotiation. Almost every free and entry-paid tier in this catalogue grants internal use and withholds redistribution, which is why a working prototype can still be unlicensed.
RPC endpointalso RPC node, RPC provider, RPC URL: The URL at which a blockchain node answers remote procedure calls — on Ethereum and most chains modelled on it, JSON-RPC requests such as a balance, a block, a receipt or a contract call. It returns raw chain state, one question at a time, as the node that serves it holds that state. It is plumbing: it answers about accounts and blocks, not about markets.
Slippagealso slippage tolerance, price slippage, slippage model: The gap between the price an order was expected to get and the price it actually got, usually quoted as a percentage. In crypto the word names three different numbers: a cost a backtest assumes, a limit a DEX swap or bot order refuses to exceed, and a measurement a data vendor computes from a snapshot of the order book. A figure without saying which is not comparable.
Stablecoinalso stable coin, payment stablecoin: A token designed to hold a fixed value against a currency, usually one US dollar. In data it plays three parts: an asset whose supply and transfers are measured chain by chain, the quote currency most crypto prices are actually set in, and the collateral most perpetuals settle in. Which tokens count as one is a list each vendor draws for itself.
Taker feealso taker, taker fees: A taker fee is what a venue charges when your order executes immediately against something already resting on the book, rather than waiting there for somebody else. It is set by what the order did, not by what type it was, and it is usually the higher of the two rates a venue quotes. Most automated strategies pay it on most of their fills.
Testnetalso test network, sandbox environment: A separate copy of a venue or a chain, reached at its own address with its own keys, where the assets are virtual and nothing settles for real. On an exchange it is a clone of the trading API whose orders match only against other test orders; on a blockchain it is a second network with worthless tokens. Neither tells you how an order would have filled on the live book.
TVLalso total value locked: TVL, total value locked, is the dollar value of the assets sitting in a protocol's contracts, summed per chain and across chains. It is a definition rather than a measurement: whether borrowed coins, the protocol's own token, liquid staking or a receipt token deposited a second time are counted is a choice each data vendor makes, and it moves with token prices whether or not anyone deposited anything.
VWAPalso volume-weighted average price, volume weighted average price: The average price of a set of trades with each weighted by its size, so total traded value over total traded quantity. In crypto there is no closing bell to reset it, so every VWAP carries a window someone chose — a rolling 24 hours, a UTC day, a candle — and a market set someone chose, from one exchange's pair to hundreds of venues converted into one currency. Name both before comparing two.

A term gets a URL here only when the catalogue uses it in at least four other pages and there is more to say than the definition. The rest are explained where they come up.