Ghostscript is an interpreter for the PostScript page description language used by laser printers.
Features:
An interpreter for the PostScript (TM) language, with the ability to convert PostScript language files to many raster formats, view them on displays, and print them on printers that dont have PostScript language capability built in;
An interpreter for Portable Document Format (PDF) files, with the same abilities;
The ability to convert PostScript language files to PDF (with some limitations) and vice versa; and
A set of C procedures (the Ghostscript library) that implement the graphics capabilities that appear as primitive operations in the PostScript language.