This page is about messages, vs. documents.
Document is used here to mean something that is made for referring back to many times.
Message is used here to mean something that is made to manipulate something once.
In this sense, most movies are Documents. For example, “Star Wars” comes out, and is meant to be watched many times over.
In this sense, most things we say are Messages. For example, ThreadMode is full of one-off messages.
The decision about whether something is a “Document” or a “Message” relies, to a large degree, on scale.
Consider: Sometimes movies are said to be a “response” to another movie, or some event in the world.
Looking at the scale of millions of people, we can imagine the succession of movies to be a dialog of sorts. One movie comes, to make some point. Another movie responds to the first movie, making counter-claims. Still another movie appears, to argue against the second.
These documents, these movies, are messages, when viewed from the scale of millions of people.
But on the scale of a single person, they are just documents.
Consider: An e-mail.
An e-mail can act like a document. You can refer back to it for some details. It has a header, and all sorts of information attached to it, like a document.
But it also acts like a message. Maybe it was sent to you to ask you a question (soliciting a response,) or to inform you of something (that you then account for.) It’s a one-time thing.
Nothing is “purely document,” or “purely message.” And yet, it is a useful distinction to make. Just be sure you understand the scale that you are working in.
We can collaborate on wiki to produce documents. Sure, we have ThreadMode discussion at the bottom of pages.
But the technology itself is intrinsicly document-based.
The reason we are using wiki, rather than, say, discussion boards, is because we are interested in making documents. In a discussion board, you can only have a series of messages.
Some systems, like Scoop, start a discussion with a Document, and then continues with a bunch of ThreadMode. However, the document cannot be revised, not even by the original poster.
The article Paper Trial by Tim Berners-Lee 1999 briefly mentions “the relationship between documents (living or dead but basically bits of state) and messages (events with associated data, including typically but not essentially sender and recipient).”