Sending important documents? Learn how to password protect PDFs for extra security using easy steps with Adobe Acrobat and free online tools.

To password protect a PDF in Adobe Acrobat Reader, you'll need the paid Pro version, which starts at $14.99 a month.

Don't let your sensitive data fall into the wrong hands. These tools encrypt important PDFs without the need to spend hundreds of dollars on the full Adobe Acrobat program.

To make use of the encrypted PDF capability, the e-mail recipient will need to have a Web browser and standard PDF reader such as Adobe Acrobat.