Ghostscript is a suite of free software based on an interpreter of the Adobe PostScript and PDF page description languages. It is highly configurable and can be used as a:
- Raster image processor (RIP) for raster printers.
- Raster image processor engine behind PostScript and PDF viewers.
- File format converter, such as PostScript to PDF converter.
- General purpose programming environment.
Several GUIs have been written for use with Ghostscript which permit a user to view a PostScript or PDF file on screen, scroll, page forward and backward, and zoom the text as well as print single or multiple pages.
- Ghostview runs under Unix/X11
- GSView runs under Windows and OS/2
Ghostscript was originally written by L. Peter Deutsch for the GNU project, and released under the GNU General Public License; later, Deutsch formed Aladdin Enterprises to commercially license Ghostscript. It is currently owned by artofcode LLC, led by Raph Levien, and maintained by the user's community and Artifex Software, the exclusive licensing agent for Ghostscript technology.
There are several variants of Ghostscript:
- AFPL Ghostscript (formerly Aladdin Ghostscript) is the current version distributed by Artifex Software and artofcode LLC, available under the Aladdin Free Public License, which allows modification and redistribution for non-commercial purposes. Commercial licenses for AFPL Ghostscript are also available.
- GPL Ghostscript (formerly GNU Ghostscript; it is no longer part of the GNU project) is available under the GNU General Public License. Generally, each version of AFPL Ghostscript is rereleased as GPL Ghostscript one year after its initial release.
The GPL version is also used as the basis for a Display Ghostscript, which adds the functionality needed to fully support Display PostScript.