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.

Q: Sometimes when I try to open a file or e-mail I get the message: "The selected file has an extension (PDF) that is not recognized by Windows Media Player but the player may be able to play it.

The Portable Document Format makes it possible for you to open and view documents, no matter what operating system, software or computer you have. To make this happen in Yahoo Mail, the email program ...

The software Google's browser uses to show PDF files has been proprietary for years, but now it's an open-source project called PDFium that others can scrutinize or use themselves. Stephen Shankland ...

If you have Microsoft Word installed on your computer, you can directly open PDF files in Word. Just open Word, click on "File," then "Open," and select your PDF file. Word will convert it into an ...