What's REST? Representational State Transfer (REST) is an architectural style consisting of a coordinated set of architectural constraints applied to components, connectors, and data elements, within a distributed hypermedia system.
The term representational state transfer was introduced and defined in 2000 by Roy Fielding in his doctoral dissertation at UC Irvine. If you want to know more about REST, I strongly suggest you read Fielding's dissertation here: https://www.ics.uci.edu/~fielding/pubs/dissertation/rest_arch_style.htm.
So, how do you build a RESTful system in Delphi? There are a lot of solutions but, according to the mentioned definitions, RESTful is not a set of libraries or algorithms, it is an architectural style, and as such, it can be respected 100%, 60%, 30%, and so on. There is a sort of scale used to...