The first document in our book file is a title page. We use the paragraph tag Title in that document only. Is there a way to create a variable in the remaining documents that reference that paragraph tag that is only used in that first document?
No, you can't reference that initial paragraph with a variable, but you can set up a variable in your template that stores the value for all docs, including the title page. By doing this, if you ever need to change the title you can change the variable value in your template and import variables across all your docs.
You can also create a MIF file of just the Title variable and import that file into all docs. This technique is in the MIF chapter of FrameMaker - Working with Content.
You can also cross-reference the Title paragraph in the other chapters of the book.
Thank you for the quick reply!
re: We use the paragraph tag Title in that document only. Is there a way to create a variable in the remaining documents that reference that paragraph tag that is only used in that first document?
If the goal is for the title text string to be defined in only one place, and then, wherever else needed, for the remaining instances to be informed/updated by the defining instance, a variable imported book-wide will do that, as TCT points out.
Another way is by cross-reference. This tends to work well for document titles, as you usually want to be referencing the entire ¶Title paragraph content. It does, however, create a hypertext link, so anyone clicking on that text in chapter 13 of the PDF/ebook/webpage is apt to suddenly find themselves on the front cover.