How to Password Protect a PDF on Mac Protect your PDFs from unauthorized access! by: Yash Wate - Last updated on: March 12th, 2021 Key Takeaways PDFs let you present documents with text, images, and rich media. And since this can sometimes hold sensitive information, it is necessary to password-protect PDFs. Password-protecting a PDF prevents unauthorized access and unauthorized editing and printing of its content. Apple’s Mac offers three native ways to password-protect a PDF, so you don’t need to download third-party software. PDF or Portable Document Format is a file format that allows you to present documents featuring text, images, and rich media with other people. In fact, it is one of the widely-accepted file formats used to share documents, which can be created and accessed independently of the platform. So you can create a PDF on one operating system and access it on the other — without having to worry about the device and the operating system you are using.