These files are also sometimes also called 'Acrobat' files, from the name of Adobe's PDF software.

The Xpdf project also includes a PDF-to-PostScript converter, PDF text extractor, and various other utilities.

Xpdf runs under the X Window System on UNIX, VMS, and OS/2. The non-X components (pdftops, pdftotext, etc.) also run on Win32 systems and should run on pretty much any system with a decent C++ compiler.

Xpdf is designed to be small and efficient. It can use Type 1, TrueType, or standard X fonts.