HP PCL/PJL reference (PCL 5 Printer Language) - Technical Reference Manual Part II
EN  Glossary-13
Serial I/O 
An input/output (I/O) interface that transmits information bit-by-bit (in 
“serial” mode). RS-232 is an industry-wide standard form of a serial 
interface.
Soft Font 
Soft fonts are fonts stored on disks. These fonts can be transferred to 
the printer’s memory and used the same way as cartridge or resident 
fonts.
Spacing 
Fonts have either fixed or proportional spacing. Fixed-spaced 
fonts are those for which the inter-character spacing is constant. 
In proportionally-spaced fonts, inter-character spacing varies with 
the natural shape of a character.
Stroke Weight 
Stroke weight describes the thickness of the strokes that compose 
characters. Medium and bold are examples of stroke weights.
Style 
Font style is defined by the angularity of the strokes of the characters 
with respect to the X-axis. Upright, italic, and condensed are 
examples of font styles.
Symbol Index 
This is a grouping of symbols. An unbound font has the capacity to 
be bound to a set of symbols selected from a complementary 
Symbol Index (such as the Unicode or the MSL symbol indexes). 
Each symbol in the index is identified by a unique symbol index 
number. Appendix D of the PCL 5 Comparison Guide contains lists 
of MSL and Unicode symbol index characters and their numbers 
(also see Unicode or MSL).










