A quick reference guide to GDI, PCL and Postscript printing for photocopiers and printers.

• GDI print emulation (or UFRII for Canon photocopiers). GDI is short for Graphics Device interface and is exclusively used by Microsoft Windows products, this means only windows applications can print or send to GDI enabled devices. Generally if you are using a different operating system you will not be able to use this type of print system. GDI printing essentially borrows the host computers processing power to render and prepare the image for printing. GDI printing is often slower and usually lacks the advanced functions of PCL.
  
• PCL print emulation. PCL is short for Printer Command Language and is the industry standard for general printing. PCL will work with most operating systems and is usually able to be configured to use all the available functions of the printer or copier. Functions like selection of different paper trays, duplex (double siding), staple sort and collate to name but a few. There are many versions of PCL and this is because it has evolved to keep pace with the latest print systems and technology.
  
• Adobe Postscript emulation. Postscript is an advanced printer language that is usually used when a high quality graphic and text output is required. GDI and PCL printing will produce a lower quality image, or may not be able to produce a certain font, especially on networked machines. Most printers and copiers need to be postscript enabled with a card or PCB, as well as the postscript driver on a computer to allow postscript printing.