HP PCL 5 Reference Manual page 161

Symbol Collections
The symbols in an unbound font (typeface) can be divided into
symbol collections. These symbol collections identify the symbols
according to some language basis or special application usage.
Some symbol collections include: Basic Latin, East European,
Turkish, Math, Semi-Graphic, and Dingbats. If a symbol collection is
included in an unbound font, all of the symbols of that collection are
included.
Note See Appendix D in the PCL 5 Comparison Guide to identify symbols
in the various collections.
The symbols within a symbol collection do not change from one
unbound font to the next. For example, the Basic Latin collection
always contains the same symbols. Different fonts may contain
different symbol collections. For example, the internal Univers
typeface contains the Latin, Math, and Semi-Graphic collections
(these collections contain all the symbols required for the 35 symbol
sets that Univers supports). The ITC Zapf Dingbats typeface, on the
other hand, contains only the Dingbats collection, which includes all
the symbols required for the five supported symbol sets.
When searching unbound scalable fonts (during font selection) for
those that match the requested symbol set, the printer actually
searches for symbol collections. To identify symbol collections which
meet the needs of the requested symbol set, the printer uses two
numbers: the Character Requirements number and the Character
Complement number.
EN
Unbound Scalable Fonts 9-9