Sitefinity has been an API-first CMS since the v4.0 release all the way back in 2010 when the content management was completely detached from the page and template editing. The page layout and the widgets created by designers and developers consume the content created by editors. Alongside the native data services, Sitefinity provides a robust set of OData Rest APIs for all prebuilt and dynamically created content types in the system.
OData is a powerful open-source and open protocol technology that defines a set of best practices for building and consuming RESTful APIs. Client applications such as SPAs, mobile apps, IoT devices can easily consume content by using a standardized REST API calls or by taking advantage of the Sitefinity WebServices SDK.
Introduced in Sitefinity 12.2, OData services can also be used to retrieve metadata such as web page structure and use this metadata to build applications that consume the page layout and content created in the CMS. This approach is the foundation of the new out-of-the box frontend layer of Sitefinity built on .Net Core.