Much like many things in the technology industry, PDF were developed by a proprietary company. Adobe Systems is the company that has many locked down IP (Intellectual Property). Adobe first release PDF back in June 1993. So as a result, the tools to work with PDF are fewer than one might like. We will cover some free options that allow you to edit PDFs in Linux for the better. Not all will be open source, but will be free to use. From editing PDF to creating volumes on a subject of interest. We will go over the installation and use of Okular, Master PDF Editor, PDF Mix Tool, PDF Chain, and last but not the least PDF Slicer. Let’s get right into it, and hack some PDF.