PostScript Language
Defacto standard method of communicating pages to output devices. PostScript is a graphical programming language. Programming languages are either compiled (e.g. Fortran or C) or interpreted (e.g. Basic or Java).
- A compiled program can be run many times and be transferred to another computer as a executable and run.
- An interpreted program is executed as it is interpreted.
- PostScript is interpreted.
- PostScript is usually generated by another program such as a printer driver. Other printer control languages such as HP's PCL are of less interest since they are more device dependent.
- PostScript Level 2 was introduced in 1990. New features of Level 2 were
- Memory management - reduced chances of memory limit being reached.
- Color Handling - Use CLUT and CIE spaces.
- Forms cache and patterns - stores repeated page elements (borders, logos, tints, etc.) in memory.
- Dictionary - Lookup table which holds parameters such as screening parameters (frequency, angle, shape).