Printer Command Language

Printer Command Language, more commonly referred to as PCL, is a page description language (PDL) developed by Hewlett-Packard as a printer protocol and has become a de facto industry standard. Originally developed for early inkjet printers in 1984, PCL has been released in varying levels for thermal, matrix printer, and page printers. HP-GL/2 and PJL are supported by later versions of PCL.

PCL is occasionally and incorrectly said to be an abbreviation for Printer Control Language which actually is another term for page description language.

PCL levels 1 through 5e/5c are command-based languages using control sequences that are processed and interpreted in the order they are received. At a consumer level, PCL data streams are generated by a print driver. PCL output can also be easily generated by custom applications.

HP introduced PCL 6 around 1995 with the HP LaserJet 4000 series printers. It consists of:

PCL 6 Enhanced features a new modular architecture that can be easily modified for future HP printers; faster return to application; faster printing of complex graphics; more efficient data streams for reduced network traffic; better WYSIWYG printing; improved print-quality; and complete backward compatibility. In early implementations, HP did not market PCL 6 well, thus causing some confusion in terminology. PCL XL was renamed to PCL 6 Enhanced, but many third-party products still use the older term. Some products may claim to be PCL 6 compliant, but may not include the PCL 5 backward compatibility. PCL 6 Enhanced is primarily generated by the printer drivers under Windows and CUPS. Due to its structure and compression methodology, custom applications rarely use it directly.

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