WebDAV servers support resource discovery through the use of the PROPFIND request method. PROPFIND is used to retrieve properties, or metadata, about a resource. When a PROPFIND request is made to a WebDAV server, the server responds with a list of properties that are supported by the resource. This allows clients to discover information about a resource, such as its creation date, last modified date, author, and other custom properties that may have been added. Additionally, WebDAV servers may support the OPTIONS method, which can be used to discover the capabilities of a server, including support for specific methods, authentication schemes, and protocol extensions. This information can help clients develop more advanced functionality and better understand the capabilities of a server.