At some point you’ll likely need to send someone a file that contains sensitive information, such as tax information, financial details, your Social Security number, or other confidential data.

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

You don't need the full Adobe Acrobat Pro just to sign a PDF. The free Adobe Acrobat Reader can easily handle that job.