RESTful APIs

The term REST was suggested by Roy Fielding in his Ph.D. dissertation in the year 2000. It stands for Representational State Transfer and is described as:

"REST emphasizes scalability of component interactions, generality of interfaces, independent deployment of components, and intermediary components to reduce interaction latency, enforce security and encapsulate legacy systems."

Having an API that conforms to the REST principles is what makes it RESTful.

URIs

One of the main components in the HTTP protocol is a URI. URI stands for Uniform Resource Identifiers and is the method by which you will access the API. You may be asking what the difference between a URI and a URL (Uniform Resource Locator) is? When I started to write this chapter, I wondered about this myself and did what any self-respecting developer would do, which is to head over to Stack Overflow. Unfortunately, my confusion only grew as there were lots of detailed answers, none of which I found particularly enlightening...