Need to add text to a PDF that doesn't support editing? No problem -- and no extra software required.

The best PDF editors allow you to edit, create, alter, and convert PDF files just like you would with any other text document. Adobe Acrobat is the most well-known option for most people.

You've filled out a PDF form in Preview and sent it to a colleague or friend, but they report the form's empty. What gives? Dan Moren's got the skinny and the fix.