[toyg]

It's like the extremely popular Pokeapi (https://pokeapi.co) or SWAPI (https://swapi.co): a service providing data over a REST interface. In other words, an API.

It's honestly the first time I see anyone claiming "an API is not an API unless it changes something".

[mikekchar]

API stands for "Application Programming Interface". A website that serves up data is not an API. The best way to explain the difference is that you can write an API on a piece of paper and it is still an API (i.e., you don't have to implement it). It documents how different parts of an application interface with each other. Normally it consists of things like the definitions of functions that you can call to achieve various results.

An API is specifically not a service. You can have many services that all use the same API. REST itself is an API. You can build another API on top of REST. So if someone says they have a REST API for querying movie information, that's sensible. If you have a service that serves up movie information, that's not an API. That's a service. It uses an API.

It might seem pedantic, but I have talked with otherwise talented programmers who didn't actually know what an API was. They mentioned using "the API" in their front end code and when I asked the only reasonable question, "Which API?" they didn't know how to respond. They've got about a billion libraries in their front end code (like everyone else ;-) ) and each one of them has an API -- otherwise they couldn't use it. However "API" only meant talking to the server to them.

I realise common usage is trumping the original definition of the term, but I think that's to the detriment of everyone involved.