9
cept. Readers who are familiar with the fields of typography and graphic design may be
content to use only the alphabetic listing, whereas others may find the systematic listing
of equal utility.
When using either listing, keep in mind that only terms in boldface have been se-
lected for use in indexing or cataloging.
Extending the thesaurus
From time to time, users may encounter terms not included in the TGDT that nonethe-
less fall within its scope; they may choose to use such terms, but if so they are encouraged
to use them provisionally while submitting a new term request form, found in Appen-
dix A.
Appendix B describes the five classes of identifiers that are listed alongside preferred
terms in the TGDT.