Web Application Description Language (WADL) is an XML description of HTTP-based web applications such as RESTful web services. WADL was submitted to the World Wide Web Consortium (W3C) by Sun in 2009 but has not been standardized yet.
WADL models the resources provided by a RESTful web service with relationships between the resources. It also allows you to clearly represent the media types used for the request and response contents.
The WADL schema that you use for building a WADL file is based on the WADL specification. Here is a quick overview of the WADL file content that describes RESTful web APIs.
The top-level element in a WADL document is the application. It contains global information about RESTful web services, such as links to schema definition and documentation. Here is a quick summary of the elements that you see in WADL: