# Controlled Vocabularies

OpenActive uses a number of [Controlled Vocabularies](https://en.wikipedia.org/wiki/Controlled_vocabulary) (including the [Activity List](https://developer.openactive.io/guide-to-openactive-on-github/activity-list)) in order to ensure the consistency and quality of OpenActive data. These are all expressed in SKOS, and developers working on Controlled Vocabularies may thus also wish to review [OpenActive's `skos` repos](https://developer.openactive.io/guide-to-openactive-on-github/skos).

* [**activity-list**](https://github.com/openactive/activity-list)**:** The code used to parse Activity List data and present it via the web front-end.
* [**accessibility-support**](https://github.com/openactive/accessibility-support)**:** A small JSON-LD vocabulary describing different classes of impairment.
* [**facility-types**](https://github.com/openactive/facility-types)**:** A JSON-LD vocabulary describing leisure centre and sport facilities.