APP has the intention to enable creation and editing of Web resources in a standardized form. APP describes a programming interface that builds on the principles of REST. URI addressed resources be manipulated, by using the HTTP verbs 'GET', 'PUT', 'POST' and 'DELETE'. The format of the transferred data is defined by the complementary Atom Syndication Format. This format allows you to embed XML-compliant content that describe itself with the help of XML schemas.