What is the Order Book?

Published on: July 2, 2025

If you are a trader or investor in the stock market, the term “order book” is something you will likely encounter frequently. But what exactly does it mean?

An order book is a real-time electronic list of all buy and sell orders for a particular stock, commodity, or ETF that the dealer or trader has entered. It can be executed, pending, cancelled or rejected. The shortcut key to open the window is F3.

Typically, the order book is displayed on a trading terminal or platform, providing key information about pending buy and sell orders. Let’s break down its core components and explain how they function.

Key Components of the Order Book

The order book is organized in two main sections:

1. Exchange

The exchange can be the NSE or BSE for equities or ETFs, and the MCX for commodities.

For Futures & Options in NSE & BSE, it will be NFO & BFO.

• Symbol

The symbol refers to the stock or commodity ticker that the user trades.

• Product

There are two types of products for order:

CNC orders (Cash and Carry orders) are used for purchasing stocks for delivery in the cash segment.

MIS orders (Margin Intraday Square-off orders) are used for intraday trading, allowing traders to buy or sell stocks on margin, with positions required to be squared off by the end of the trading day.

• Buy/Sell

The order book highlights B as Buy order and S as Sell Order.

• Quantity – Number of quantity to be executed.
• Price at which the user enters the order.
• LTP – Last Trade Price
• Order – MKT stands for Market Order and LMT for Limit Order
• Status – Complete (Executed), Pending or Rejected (for non-availability of funds or beyond Daily Price Range)
• Date & Time – Date & Time of order entered.
• Order ID – Reference number for the order
• Exchange Order ID – Reference number by Exchange for the order
• Order Source – It can be from Zone Mobile, Zone Web, Trade Point or if the user has created a SIP order.

How Does the Order Book Work?

• If you place a buy limit order for a stock at Rs. 100, your order will stay in the order book until the stock’s price reaches Rs .100.
• If the price is higher than your limit price, your order will remain unfilled until the price reaches your desired level.
• If someone else places a sell limit order at Rs.100, your buy order could be matched with that seller, executing the trade.

You can also read about the Types of Orders here.