I found through a lot of web searching the following information so I have put it together in this tip.
PCL(1) through PCL4 (OLDER PCL), Will not be listed as it was for HP Laser printer seriesII and older. When a new version of PCL was developed it included commands not found in the previous versions, as well as the previous PCL commands. BUT with PCL 6 it has new architecture that is designed to be able to be modified for future HP printers. A major compatibility issues have caused a lot of users to choose PCL 5 drivers instead of the PCL6.
PCL 5 was introduced for the HP Laser III family of printerÆs, PCL 5 had/has the best publishing functionality for the office environment. It development was to enable a larger compatibility for font scaling. It is mainly used for desktop publishing, and presentation applications. Today it is still the most widely used version of PCL.
PCL 5E & PCL5C was released for the HP series5 lasers and colour printers respectively. A major change was bidirectional communication between the printer and the computer. The font selection was also greater, as programs were developed for MS Windows. The C Enhancement added colour support for HP printers.
PCL 6 Has major changes, there are backward compatibility problems, as PCL6 is extremely different from previous PCL versions. A major difference is the way it sends commands to the printer. It was developed by HP to increase performance and reliability (Yeah Right).