REST backend vs REST API (or API Backend)

Question

I'm working on an application running on Google App engine (python) with the frontend in AngularJS framework. The backend of this app simply returns the relevant data as JSON upon a GET for example, the URL routes for which are configured in the frontend (as services etc). That is, the standard CRUD operations are performed using the HTTP verbs, which i think is the main idea of a REST backend.

What i'd like to know is how is this backend different from a REST API? What i can make out by myself is that an API returns data similar to a response from a backend but it also sends more information about the various options/available actions the client has at any given moment. Is this the right idea? If so, how would you go about using this information? Wouldn't the application using this API become highly coupled with it?

And if i have to convert the REST backend to use the API, what benefits would i get. Docs about REST API say that it makes it easy for app on different platforms to access the data uniformly (like here ). But the same thing can be done by a simple REST backend since the data itself is platform agnostic and as long as we can write a frontend to handle the data properly on each platform.

Answer 1

If it's a REST service that's only used by a single application I'd typically call that a back-end. If it's shared for multiple applications I'd probably call it an API. Really it's two different names for the same thing.