Portable document format (PDF) files remain a popular choice for business documents ranging from contracts and forms to manuals and reports, so there's a good chance you need to open them often.

When somebody sends you a document as an attachment, don't just open it. Use the free tool Dangerzone to scrub it clean of any malevolent code. Here's how it works. You probably already know it's ...

Gimp is normally used to create or manipulate images files, but can also work with PDFs if you understand how it works and what it's limits are. If you’ve never used Gimp—a free image editor available ...