# Order Book ### What is an Order Book? An Orderbook is an trading protocol, used primarily in the stock exchange but has recently been an emerging presence in the crypto space. A *matching engine* uses this to determine which orders can be fully or partially executed. #### Buy and Sell The two main participants in an order book are the 'buyer' and the 'seller'. The buyer (the 'buy') bids for a certain amount of tokens at a specific price. This demand is then satisfied by the seller (the 'sell'), who asks for a particular fee for their tokens. A list of 'buys' and 'sell(s)' is generated with the matching engine pairing deals that satisfy both parties. #### Visual Representation An *order book depth chart* dynamically shows the list of bids and asks for a specific commodity. A general rule of practice is that the buys are shown on the left and the sells on the right.

Figure 1 - An Order book depth chart shows the buys in green, and the sells on the right are in red. The x-axis is the unit price; the y-axis is cumulative order depth (https://en.wikipedia.org/wiki/Order_book#/media/File:Order_book_depth_chart.gif)

#### Order Book Terminology **Price Point** When multiple orders are the same price, they are referred to as a *price point*, meaning that if a bid comes at that *price level*, the sell orders could potentially fulfil it. **Top of the book** The top of the book is the highest buy and the lowest sell. **Book depth** The book depth is the number of price levels available at a particular time. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.candyswap.gg/information/order-book.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.