> For the complete documentation index, see [llms.txt](https://help.topstepx.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://help.topstepx.com/components/dom/market-data.md).

# Market Data

### Data Structure

TopstepX uses Explicit Book for market data on the DOM versus displaying an Implied Book.

In futures trading, the implied book and explicit book are two different components of market data that provide information about orders and prices.

**Explicit Book**: The explicit book contains actual orders that traders have directly entered into the market. These are real, visible bids and offers that participants have explicitly placed.

**Implied Book**: The implied book contains synthetic orders based on relationships between different contracts or trading strategies. These orders are not directly entered by traders but are derived from other existing orders, including options strategies.

Key differences:

1. Explicit orders are user-generated; implied orders are system-generated.
2. Explicit orders are directly visible; implied orders are derived.

### Level 1 / TOB

By default, most traders will have Level 1 or 'Top of Book' data only. This provides a single level of market data, showing the best bid and best ask price. While still fully able to trade and make informed decisions, it does lack in full context of the buyers and sellers in the market:

<figure><img src="/files/e3M7Tc08ArEiQpQ6O0Be" alt=""><figcaption><p>Level 1 / "Top of Book"</p></figcaption></figure>

### Level 2 / DOM

Level 2 data, also known as Depth of Market (DOM) or price ladder, provides more comprehensive market data by displaying multiple levels of bid and ask prices. This allows traders to view the full range of buy and sell orders in the market, offering deeper insights into market depth and liquidity. With Level 2 data, traders can make more informed decisions by understanding the supply and demand dynamics at various price levels. \
\
**Note:** Level 2 is typically an additional add-on ($), please check with your firm:

<figure><img src="/files/X2Z0TC7mamUwh7hXHWDV" alt=""><figcaption><p>Level 2 / "Depth of Market"</p></figcaption></figure>


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