[quineoa]

Isn't Reddit like this, in a way? You can append ".json" at the end and get the data for a page. Others can build their own UI on top of this, if they don't prefer the first party representation.

https://www.reddit.com/r/pics/.json

[Felk]

The same could be achieved by having the server return different views of the data for different HTTP Accept headers, although not as convenient as appending a file extension. I once did this to interpolate REST API responses into dedicated HTML templates if requested with Accept: text/html, which made exploring the API in the browser more enjoyable.

[zdragnar]

If you go back to the web as a bunch of file servers, where every URL ended in the extension type of the document you wanted, this is what you get. Then MVC frameworks said "hey, if the URL represents some semantic aspect of the View, we can show off the power of MVC by letting users swap out the view by changing the extension!" And voila, some.com/url.html for HTML and some.com/url.xml for XML and, later, some.com/url.json for JSON

Most of the big MVC frameworks offered this out of the box at some point, which made life easier before dedicated RESTful APIs became a thing.

[gpnt]

Yeah, it is kind the same, but with the same page.