Using entities, conrefs, or reusable text for product name (for example)

[JFB]

This is a newbie question so bear with me, I've used DITA but new to XMetal:

What's the best way to create a "variable" as they're called sometimes elsewhere, to insert things like a product name and be able to change it in a referenced file to change throughout a book?

I first learned to do just reusable text and insert it, then found that I can create text entities which seems better (mainly because all of them are there in a list when inserting) but in using entities, if I create one in a given doc, it only seems available to that doc. To have it available to the whole project (map, bookmap, etc) do I need to insert it in the DTD somehow? Is there somewhere else to store it to make it available as a referenced entity for an entire Ditamap?

Using XMetal 6.0 with DITA, generic straight as it comes.

[Derek Read]

It is generally considered a best practice to not use text entities with DITA. DITA specifically provides "content referencing" (via an attribute called "conref") for what you wish to do. This is generally referred to simply as "conref" in the DITA community.
Please look for "conref" and "reusable component" (our specific term) in the XMetaL Author Enterprise help.

[JFB]

Thanks Derek, that's just what I needed to know.