REST (Representational State Transfer) refers to a way of exchanging data between different systems. The REST exchange is possible though various methods: GET, POST, PUT, PATCH, DELETE, HEAD, OPTIONS, CONNECT and TRACE. REST can be divided into different levels from 0 to 3. Level-0 describes a simple XML exchange and LEVEL-3 the HATEOAS (Hypermedia As The Engine Of Application State) approach, which returns its resources (LINK) in the response to the client e.g. after creating (POST) a blog post.