What is a PDF file type?

When working with PDFs, it’s important to know what PDF file type you’re using. Many of us may only be familiar with the ‘traditional’ PDF format, which is commonly used for saving documents online. But there are a variety of PDF types, each with their own function.

Some of these formats are based on International Organisation for Standardisation (ISO) standards, while others are based on standards adapted by additional organisations. Let’s take a look at the different PDF types below and where you may encounter them.

What are the different PDF file types?

There are nine different PDF types:

  • PDF. This PDF file type is seen as the ‘standard’ PDF format. It is often used for sharing and viewing files online.
  • PDF/A. This type of PDF file is often used by managers and archivists who require long-term file storage. It also has a restricted set of features, including JavaScript, audio and video content.
  • PDF/E. This format supports construction, engineering and manufacturing specifications and is often used in those industries.
  • PDF/X. Commonly used by graphic designers and print professionals, this PDF file type is designed to better support graphics when sharing and printing.
  • PDF/VT. This file is similar to the PDF/X format but features additional customisation features. Again, the PDF/VT file type is most suited to print professionals and graphic designers.
  • PDF/UA. This type of format is compatible with assistive technology, enhancing readability and navigation for people with disabilities.
  • PAdEs. Sets the standards for PDF Advanced Electronic Signatures in line with major legislation.
  • PDF Healthcare. This standard was developed to secure best practice for handling and managing healthcare information.
  • Searchable PDF. A searchable PDF is essentially a standard PDF file with a search function. The basic function of a searchable-PDF is to make image-based PDFs text-searchable.

Seven of these are based on ISO standards:

  • PDF
  • PDF/A
  • PDF/E
  • PDF/X
  • PDF/VT
  • PDF/UA
  • Searchable PDF.

While two of these have been adapted by additional organisations to fit their specific needs:

  • PAdES
  • PDF Healthcare.

History of PDF files

Adobe Inc. invented the PDF - or Portable Document Format - in the early 1990s, introducing it to the world at the Windows and OS|2 Conference in January 1993.

It remained a proprietary format until it was released as an open standard in 2008, maintained by the International Organisation for Standardisation (ISO).

PDFs continue to be the go-to file type to present and exchange documents reliably — independent of software, hardware or operating system.

Read more on the history of the PDF.

What are PDF file types used for?

PDFs have many capabilities. To fully understand these, it’s important to familiarise yourself with the PDF file type you’re working with. Generally, however, the suite of PDF based extensions can be used for the following:

  • Maintaining document formatting. PDFs are a portable document format. This means they can be used to maintain important information from the file, such as text formatting, images, hyperlinks and comments.
  • Share and view files effortlessly. The standard PDF format is compatible with most computers and devices. This makes it easy to open and share your files across the web, without having to worry about compatibility restrictions.
  • Secure confidential documents. You can protect sensitive information with PDF documents. Simply lock your file for viewing or editing by setting passwords and restricting certain features.
  • Send, receive and manage electronic signatures. With a PDF document, you can quickly sign, send and receive electronic signatures, without the need for printing.

Manage your documents effectively

With Adobe's collection of free online tools. You can easily edit, sign and add pages to your PDF documents today.

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Advantages of PDF file types

When working with or accessing different types of PDFs, there are many advantages to make the most of:

  • Universally compatible. Standard PDF files can easily be opened and viewed across most devices. So, when you send a PDF file to someone, they should be able to view it without any problems.
  • Accessible to a wider audience. An accessible PDF document (PDF/UA) can be read and accessed by people with disabilities, such as those who are visually impaired or rely on assistive technologies.
  • Suited for specialist uses. Specific PDF file formats can be ideal for specialist industries - such as PDF/A for archiving, PDF/E for engineering and PDF/X for printing.
  • Take up less hard-drive space. PDF files are compressed, which means they tend to be smaller than other file formats. This can be a great draw if you’re looking to save on hard-drive space.
  • Great for sharing and collaborating. Because PDF files are typically smaller than most other formats, you can easily share files via email or upload them online.
  • Easy to create and edit. PDF files are simple to create with Adobe Acrobat. You can also easily convert other document formats, such as .DOCX or DOC, to a PDF file in minutes, using the Adobe Acrobat online convert to PDF tool.

Find out more about different types of Document File and their uses, with Adobe.

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PDF file types: FAQs.

What does PDF stand for?

PDF stands for Portable Document Format. PDFs allow users to transfer documents between different operating systems and programmes and maintain consistency. Its fixed formatting made digital documents ‘portable’ for the first time.

What is the best PDF format to use?

The best PDF format to use will depend on your individual requirements. For example, if you’re a graphic designer looking to create high-quality documents, then the PDF/X file type is a great option. This PDF standard will optimise your documents so that they are print ready. But if you’re just looking for a format that’s easy to create and share documents, then you may want to opt for a standard PDF format.

What is the most common PDF format?

The classic PDF or Portable Document Format, is the most common PDF format. This format is generally seen as the standard format for creating and sharing documents online. PDF files can also be opened and read across many devices, making them a popular option.

What is the standard PDF format?

The Portable Document Format (PDF) is the standard PDF format. Adobe created the format to give people an easy way to create and share documents online, regardless of the type of software or operating system they are using.

What PDF file type is best for printing?

PDF/X and PDF/VT are the best PDF file types for printing. These PDF file types are often used by creative professionals and graphic designers for printing personalised marketing materials and other high-quality, print-ready documents.