Any arbitrary piece of text and/or graphics in a WordprocessingML document can be assigned a name, called a bookmark. If a bookmark references text that represents an expression, that bookmark's name can be used as an operand in another expression. If a whole field is bookmarked, its bookmark name can also be used as an operand in an expression. [Example: Given that X is a bookmark for the text 4, Y is a bookmark for the text 2, and Result is a bookmark for the following field:

=X + Y

the field

=Result * 10

has the result 60. end example]