---
id: education_item.price-and-market-mechanics
page_type: education_article
title: "Order Book, Price and Market Mechanics"
description: "Order book and market mechanics: price and market price, volatility, liquidity, bids and asks, limit and market orders, and the spread."
section: education
category: "Key Terms and Concepts"
url: https://moonbot.eu/en/education/key-terms-and-concepts/price-and-market-mechanics?format=md
locale: en
alternate_ru: https://moonbot.eu/education/key-terms-and-concepts/price-and-market-mechanics?format=md
parent: https://moonbot.eu/en/education/key-terms-and-concepts?format=md
previous: https://moonbot.eu/en/education/key-terms-and-concepts/basic-concepts-of-the-crypto-market-and-trading?format=md
next: https://moonbot.eu/en/education/key-terms-and-concepts/orders-and-trade-execution?format=md
status: published
updated_at: 2026-10-19T04:25:31+03:00
---

# Order Book, Price and Market Mechanics

- **Price**\
  the value of an asset expressed in another asset or currency within a trading pair.
- **Market price**\
  the best available buy or sell price of an asset at the current moment, formed by the orders in the order book. The market price is not an average or calculated value and may change as new orders appear.
- **Volatility**\
  the degree of price fluctuation of an asset over a certain period. High volatility means sharp and frequent price movements, while low volatility indicates smoother and more stable trends.
- **Liquidity**\
  a market characteristic that reflects how quickly and easily an asset can be bought or sold at the market price without significantly affecting it.
- **Order Book**\
  also known as the “**market depth**” - a table of all active **limit orders** to buy and sell an asset. It displays **market depth** (the number and volume of orders at different price levels) and **liquidity** (the ability to quickly execute trades without significantly impacting the price). The larger the order volumes in the order book, the deeper the market and the higher the liquidity - meaning large trades can be executed with minimal slippage (the term "slippage" is explained below).

How to read a stock market order book: focus on the distribution of bids and offers across price levels, as well as their volumes and density. This allows you to assess the balance between supply and demand and predict the most likely direction of price movement.

**The Order Book is divided into two parts:**

- **Bids** - buy orders placed below the current price. These are usually displayed in **green**. Bids show the price and volume at which buyers are willing to purchase an asset.
- **Asks** - sell orders placed above the current price. These are usually displayed in red. Asks show the price and volume at which sellers are willing to sell an asset.

Bids and asks are the basic components of the order book: bids represent demand, whilst asks represent supply, and the balance between them directly influences short-term price movements.

All bids and asks in the order book are **limit orders**. There are two main types of orders:

- **Limit order** - an order to buy or sell at a specific price set by the trader. For example, if you want to buy Bitcoin for no more than 90,000 USDT, you place a limit order at that price. The order enters the order book and waits to be filled when the market price - meaning the best available ask in the order book - reaches or falls below your specified level. Note: "***Market price**" in this context refers to the* ***best available ask in the order book at the current moment**, not an average or calculated value.*
- **Market order** - an order to buy or sell immediately at the best available price. A market order does not enter the order book - it is executed instantly by "consuming" existing limit orders in the order book. Advantage: guaranteed execution. Disadvantage: the execution price may differ from the expected one, especially in low-liquidity conditions (slippage).

Thus, **the order book is formed by limit orders** - they create supply and demand at different price levels. **Market orders use liquidity from the order book** - they are executed against limit orders placed by other traders.

- **Spread**\
  the difference between the best bid (highest buy price) and the best ask (lowest sell price). The smaller the spread and the larger the volumes in the order book, the higher the asset’s liquidity and the more favorable the trading conditions.

Densities on the price chart are clusters of large limit orders at specific price levels, which can act as strong support or resistance levels. Traders often monitor such zones because they can slow down or reverse price movements. Large orders in the order book are particularly important: if a large volume of bids accumulates at a level, this can prevent a fall; if there are many asks, it can limit an uptrend.

Trading based on density in the order book is built on the expectation of a price reaction to such levels: for example, entering a position as the price approaches a dense area, anticipating either a bounce or a confirmed breakout. It is important to take the context into account – the news backdrop, the timeframe, overall volatility and price behaviour at neighbouring levels.

Another important analytical tool is the time and sales tape. This is a stream of executed orders that shows actual buys and sells in the market in chronological order. How to read the Time & Sales feed: pay attention to trade volumes, their direction (buy/sell), and the rate at which consecutive trades appear. A series of large buys may signal growing demand, even if there are no noticeable clusters in the order book yet. The Time & Sales feed helps distinguish "noise" from real price pressure and confirms or refutes signals received from the order book.

Together, the order book and the trade stream provide a comprehensive picture of market activity: the order book reflects participants’ intentions (limit orders), whilst the trade stream reflects their actual actions (market orders). This dual analysis helps to assess the situation more accurately and make more informed trading decisions.

We recommend that you read the supplementary material ["Order Books (ASK and BID)" >>>](https://moonbot.eu/en/documentation/main-terminal-window-with-advanced-settings/order-books-buy-and-sell?format=md)

## Navigation

Path: [Main](https://moonbot.eu/en?format=md) / [Education](https://moonbot.eu/en/education?format=md) / [Key Terms and Concepts](https://moonbot.eu/en/education/key-terms-and-concepts?format=md) / Order Book, Price and Market Mechanics

Parent section: [Key Terms and Concepts](https://moonbot.eu/en/education/key-terms-and-concepts?format=md)

Previous: [Basic Concepts of the Crypto Market and Trading](https://moonbot.eu/en/education/key-terms-and-concepts/basic-concepts-of-the-crypto-market-and-trading?format=md)

Next: [Orders and Trade Execution](https://moonbot.eu/en/education/key-terms-and-concepts/orders-and-trade-execution?format=md)

## Related

- [Orders and Trade Execution](https://moonbot.eu/en/education/key-terms-and-concepts/orders-and-trade-execution?format=md)
- [Types of Trading and Positions](https://moonbot.eu/en/education/key-terms-and-concepts/types-of-trading-and-positions?format=md)
- [Derivatives and Borrowed Funds](https://moonbot.eu/en/education/key-terms-and-concepts/derivatives-and-borrowed-funds?format=md)
- [Position and Risk Management](https://moonbot.eu/en/education/key-terms-and-concepts/position-and-risk-management?format=md)
- [Trading Strategies and Styles](https://moonbot.eu/en/education/key-terms-and-concepts/trading-strategies-and-styles?format=md)