Print processors and data types
The print processor tells the spooler to alter a job according to the document data type. It works in conjunction with the printer driver to send the spooled print jobs from the hard drive to the printer.
Software vendors occasionally develop their own print processors to support custom data types. Normally, the print processor does not require any settings or intervention from administrators.
The Windows printing process normally supports five data types. The two most commonly used data types, enhanced metafile (EMF) and ready to print (RAW), affect performance in different ways on both the client computer and the print server computer.
EMF, or enhanced metafile, is the default datatype with most Windows-based programs. With EMF, the printed document is altered into a metafile format that is more portable than RAW files and usually can be printed on any printer. EMF files tend to be smaller than RAW files that contain the same print job. Regarding performance, only the first portion of a print job is altered, or rendered on the client computer, but most of the impact is on the print server computer, which also helps the application on the client computer to return control to the user faster.
RAW is the default data type for clients other than Windows-based programs. The RAW data type tells the spooler not to alter the print job at all prior to printing. With this data type, the entire process of preparing the print job is done on the client computer.
The following table shows the five different data types supported by the default Windows print processor.