RSS / XML capabilities - Clarification please?

[bradgreens]

I've been in a debate that RSS is limited to a set of elements and not meant for streaming custom elements as anyone pleases.

I've used RSS feeds a good amount, and have never seen a bunch of custom elements added into the feed... is that possible? Wouldn't you need a custom script (PHP) to read that sort of feed (PHP XML parser). If the latter is true, why wouldn't you just use XML format?

A basic explanation is really all I'm hoping for. I've read a million RSS explanations, but someone's trying to convince me RSS can do "anything" because "it's XML".

Sure thanks because I know the question is lame.

[Alan]

Firstly, RSS is XML. RSS is a special XML document which is given a specific form for a specific function. This specific form allows it to carry out it's specific function (which is to act as a feed which readers can interpret). It doesn't get much clearer than that.

In OOP terms, a RSS object would inherit it's functionality from a XML object. It's just a more specific form of an XML document.