The humble Portable Document Format file (PDF to its mates) is one of the most versatile formats you could ask for. It solves a very simple problem: how do you ensure that a file you share with other people looks identical on their computers even if they don’t have access to the application in which it was created?

After starting off as a simple way of sharing and displaying documents in a consistent way, PDFs have evolved to become ever more useful. Armed with the right tools you can search them for specific text (then extract that text), annotate them, add comments and even use them like digital forms, filling in sections by typing text or selecting from drop-down menus. And if the PDF is a ‘true’ one (see the box right), you can even edit its content and layout. In this tutorial we’ll reveal what free PDF tools are available in Linux, plus how to use them to meet your every PDF-related need.

Creating PDFs

Before we delve any deeper, let’s quickly recap how you can create PDF files of your own. The easiest way to generate them is from existing documents. In LibreOffice, for example, choose ‘File > Export as > Export as PDF’ to generate a PDF from your Writer, Calc, Impress or Draw document. You’ll see lots of different options are available, which you’ll come to understand