Content negotiation

Serving multiple documents at the same URI

Content negotiation refers to mechanisms defined as a part of HTTP that make it possible to serve different versions of a document at the same URI, so that user agents can specify which version fits their capabilities the best. One classical use of this mechanism is to serve an image in GIF or PNG format, so that a browser that cannot display PNG images will be served the GIF version.

This keyword could refer to multiple things. Here are some suggestions: