# API reference

This section contains detailed technical information, divided into these sub-sections:

* **Booking.com codes**
Booking.com enumerations, used as values for various XML attributes.
* **OTA codes**
OTA enumerations, used as values for various XML attributes.
* **OTA objects**
XML objects (derived) from the OTA standard.


Work-in-progress
This section is a work-in-progress. The most important objects have been
documented, but you may encounter pages with missing information. We are
continuously updating the documentation and strive to make it complete
as soon as possible. If any missing information is stopping you from
integrating one of our APIs, please [let us know](https://connect.booking.com/user_guide/site/en-US/content/#support-feedback).