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IntroductionWhat Is an Order BookBids and AsksSpread and Mid PriceLimit OrdersMarket OrdersDepth and Liquidity
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DocsMarket Structure

Market Orders

How market orders consume liquidity and why they change the book differently from resting limit orders.

Market Orders

A market order does not specify a limit price.

Instead, it says:

Execute against the best available opposite-side liquidity right now.

What market orders do

Market orders **remove liquidity**.

They do not rest on the book.

That means they tend to affect:

  • recent trades
  • top of book
  • depth near the touch

Example

If you submit a market buy:

  • it trades against the best ask first
  • then the next ask if more size is needed
  • then the next level, and so on

This is often called **sweeping the book**.

Slippage

If there is not enough size at the best price, a market order may execute across multiple levels.

That creates slippage:

your execution average becomes worse than the best visible price you started with

Why this matters in the UI

A good terminal should make it obvious that market orders affect:

  • the tape
  • top of book
  • depth shape
  • the event log

more than they affect resting visible liquidity.

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What market orders doExampleSlippageWhy this matters in the UI