> ## Documentation Index
> Fetch the complete documentation index at: https://docs.trdrs.co/llms.txt
> Use this file to discover all available pages before exploring further.

# Market Data Overview

> Symbols, history, quotes, and live streams — the licensed data surface every chart runs on.

Market data is the read side of the engine: the symbol catalog, OHLCV history, batch quotes, and
two live streams over Server-Sent Events. It is public in shape but licensed in access — served to
first-party origins and authenticated callers.

## What you can build

* **A chart** — [find the symbol](/guides/find-symbols), read its tick and price format, [backfill history](/guides/backfill-history), then [stream live bars](/guides/stream-live-data). Four calls, in that order.
* **A scroll-back that knows when to stop** — `countBack` pages backwards from a timestamp, and `noData` says there is nothing older to ask for.
* **A watchlist** — batch quote snapshots for up to 50 symbols in one call, answered in request order, with a symbol that has no feed coming back all-null rather than dropped.
* **A multi-chart layout** — one multiplexed connection carries every bar subscription you hold, up to 24.
* **Synthetic instruments** — a spread expression over up to four legs, evaluated server-side, that resolves, backfills and streams like any other instrument.
* **Correct prices without hardcoding an exchange** — tick size, price format, session model and the served holiday calendar all come off the wire.
* **News and calendar surfaces** — aggregated headlines and economic events, each with its own stream.

## Core objects

A symbol row, an OHLCV bar, a quote snapshot, and the futures contract catalog. Fetch
[market-data limits](/api-reference/market-data/get-market-data-limits) once before your first
data call — it answers the questions the other routes assume.

## Where to go next

<Columns cols={2}>
  <Card title="Find symbols" icon="magnifying-glass" href="/guides/find-symbols">
    The limits, the catalog, and the tick, format and session a ticket needs.
  </Card>

  <Card title="Backfill history" icon="chart-line" href="/guides/backfill-history">
    Windows, countBack paging, and spread expressions.
  </Card>

  <Card title="Stream live data" icon="tower-broadcast" href="/guides/stream-live-data">
    The snapshot-then-events contract that heals its own reconnects.
  </Card>

  <Card title="Bring data via your venue" icon="building-columns" href="/guides/venue-data">
    Why a trader's own venue login is what serves their charts.
  </Card>

  <Card title="Publish a datafeed" icon="satellite-dish" href="/guides/publish-a-datafeed">
    Serving a market the engine does not connect to.
  </Card>

  <Card title="Streaming" icon="wave-square" href="/partner-platform/overview/streaming">
    The reconnect contract in full.
  </Card>
</Columns>