However, a little knowledge about these fields can enable you to start taking advantage of the numerous options that they offer.
You can see the REF field underlying a cross-reference by placing your cursor within the text that appears in it and pressing Shift F9, which displays the underlying field code instead of the bookmarked text.
For example, the following field code will insert the Product Name bookmark and its contents into the active document and will thus display the bookmarked text in the active document. If no bookmark is specified, the INCLUDETEXT field will insert the entire document specified.
You can also accomplish this using document properties and content controls (introduced in Word 2007).
For example, if you create a bookmark that encloses the name of a product, such as the word keyboard, and assign the name Product Name to the bookmark, and then you create a cross-reference configured as a hyperlink to this bookmark within a sentence somewhere else in your document, the word keyboard will appear at the cross-reference. Now if you place your cursor within the word keyboard and press Shift F9, Word will display the underlying field code instead of the word keyboard. This field code consists of the field name REF, the bookmark name Product Name, and the switch \h, which indicates that the cross-reference is configured as a hyperlink.
When you place your cursor over a cross-reference configured as a hyperlink and click Ctrl click, your cursor will jump to the location of the bookmark.
For more information about the STYLEREF field, see the Microsoft help topic Field Codes: Style Ref Field and Useful Style Ref Tricks by Suzanne Barnhill.
Just as you can use REF fields to repeat the content of a bookmark in multiple places in a document, you can use the INCLUDETEXT field to insert a bookmark with the text and graphics that it encloses from another document.