> For the complete documentation index, see [llms.txt](https://docs.validationcloud.io/v1/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.validationcloud.io/v1/stellar/horizon-api/order-books.md).

# Order Books

An order book is a collection of offers for a specific pair of assets.

The [latest ledger](https://developers.stellar.org/docs/data/horizon/api-reference/structure/consistency) known to Horizon is included as an HTTP header in the response.

Learn more about [order books](https://developers.stellar.org/docs/learn/glossary#decentralized-exchange).