Portable Document Format (PDF) is a file format used to present documents in a manner that is not affected by the application, hardware, or operating system used to view the document.
Initially outlined in 1991 by Adobe Systems, offered as a freely-usable but proprietary format beginning in 1993, and released as an open standard in 2008, Portable Document Format (PDF) is the format most frequently used to transmit documents in a way that isn't reliant upon any specific application, operating system, or hardware. By making PDF technology free to use, Adobe encouraged broad adoption of PDF as the go-to format for transmitting a variety of documents.
PDFs are ideally suited to meeting at least three document transmission goals:
Transmitting sensitive documents: PDFs are not as easily tampered with as other formats. As a result, many sensitive documents are transmitted in PDF format to help ensure that the recipient uses them in the form intended, and doesn't modify the formatting or content. In addition, security features such as password protection, the addition of watermarks, and encryption technologies can be used to make PDFs even more secure.
Cross-platform compatibility: Using PDF format ensures that a recipient will be able to view a document on any platform without losing data or content.
Preserving complex layouts: Documents with a complex layout, such as tax forms, as well as those made up of many different types of elements that need to remain in the same position relative to each other, such electronic brochures, are ideally suited to transmission as PDFs.
Frequently Asked Questions
What type of content can a PDF contain?
PDFs routinely include text, images, and hyperlinks. Support for these types of content is provided by virtually all PDF viewers and operating systems. Other types of content, including empty text fields (to create printable forms), video and audio clips, and Flash-based animations can also be embedded in PDFs, but support for these items is limited to specific viewing application and platforms.
Are there any risks or disadvantages to using PDFs?
There are at least three risks and disadvantages associated with using PDFs:
- First, PDFs are hard to edit. If the document being transmitted needs to be easily edited, PDF is not the right choice. While PDFs are hard to edit, they are not impossible to edit, which leads to the second risk associated with using PDFs.
- Second, PDFs give the impression of offering greater protection than they actually offer. The average computer user will open a PDF with Adobe Reader or a similar “read-only” PDF viewer. In so doing, they will realize that they cannot edit the PDF, and may assume the same to be true for other computer users. However, there are a number of programs, such as Adobe Acrobat, Nitro PDF, and Foxit Reader, that can be used to edit PDFs additional security features aren't implemented. This can potentially create a situation where an unsuspecting computer user transmits a document assuming it is adequately secured when it is still editable by a more knowledgeable computer user.
- Third, a variety of scripts can be embedded into a PDF allowing a PDF document to be infected with malicious code that will attempt to execute and exploit application-specific vulnerabilities. These types of attacks are typically aimed at users of Adobe Reader and Acrobat due to their widespread usage, though at least one attack has also targeted users of Foxit Reader.