From nakedsecurity.sophos.com
Even if you haven’t heard of the venerable Ghostscript project, you may very well have used it without knowing.
Alternatively, you may have it baked into a cloud service that you offer, or have it preinstalled and ready to go if you use a package-based software service such as a BSD or Linux distro, Homebrew on a Mac, or Chocolatey on Windows.
Ghostscript is a free and open-source implementation of Adobe’s widely-used PostScript document composition system and its even-more-widely-used PDF file format, short for Portable Document Format. (Internally, PDF files rely on PostScript code to define how to compose a document.)
For example, the popular open-source graphics program Inkscape uses Ghostscript behind the scenes to import EPS (Embedded PostScript) vector graphics files, such as you might download from an image library or receive from a design company.