HP PCL/PJL reference - Printer Job Language Technical Reference Manual

EN Glossary-3
Explicit Switching
Explicit switching occurs when a printer language is activated due to
processing a PJL ENTER command.
Factory Default
Factory defaults refer to the feature settings that are programmed into
the printer at the factory. These values are stored in read-only
memory and cannot be changed. Factory default settings are in use
unless you override them using either the control panel or by sending
printer commands.
Factory Default Environment
A factory default is a setting programmed into the printer at the
factory. The group of all the printer's factory settings is referred to as
the Factory Default Environment.
Implicit Switching
Implicit switching occurs when a printer language is activated due to
reception of non-PJL data which is not preceded by a PJL ENTER
command. (See context-sensitive printer language selection.)
Job Boundary
The beginning or end of a print job. The position between two
characters of data in the data stream where the previous character is
the last character of the previous print job, and the next character is
the first character of the next print job.
Macro
A macro is a collection of escape sequences, control codes, and data
downloaded to the printer. Its execution can be initiated using a single
command.
Modified Print Environment
Once a printer language, such as PCL, is entered, the current feature
settings constitute the modified print environment. Whenever a
feature setting is altered using printer language commands, the new
setting is recorded in the Modified Print Environment.