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What Is a PDF: Understanding the Format
What Is a PDF: Understanding the Format

What Is a PDF: Understanding the Format

by Alexa Davis
Mar 21, 2024

PDF files are everywhere and used by all sorts of people and organizations.

From user manuals to interactive forms, the PDF format has become ubiquitous in our daily lives. Yet, despite its widespread use, many may find themselves wondering: what exactly is a PDF?

In this article, we will provide detailed information about the format, its use, its advantages over other document types, and how to work with it.

What Does PDF Stand for?

The PDF acronym stands for Portable Document Format. This file type was invented by Dr. John Warnock, the co-founder of Adobe, in 1991. The PDF format we know today began under the name The Camelot Project. By 1992, this had become the PDF.

PDF has become the de facto standard for distributing electronic documents in a reliable and consistent manner. At its core, a PDF file encapsulates text, images, fonts, and other elements into a single, self-contained document that can be viewed, printed, and shared seamlessly.

Unlike other file formats that may vary in appearance depending on the application or operating system, PDFs ensure consistency in how the content is displayed. Whether it's a complex report, a brochure, or a presentation, PDFs retain the fonts, images, colors, and layout precisely as intended by the creator.

Despite being more than 30 years old, the PDF format is still going strong and is trusted by organizations worldwide.

How to Open a PDF?

Since PDFs are universal, they can be viewed on any device. There are several ways to read them and you probably already have at least one of these on your device as standard.

For example, most modern internet browsers have the feature to view PDFs. This is why when you open a PDF it will often appear as a page in an internet browser rather than a document like Word.

What is a PDF file - how to open PDF

You can also view PDFs with software or apps, like Adobe, Preview, and others. You might need to download it to the computer or the device you use.

Another way of viewing PDF files is through cloud storage services. If you store PDFs on a cloud file storage service, you’ll probably find that this already has a built-in PDF viewer. Google Drive or Dropbox can perfectly do that.

How to Edit a PDF File?

Generally speaking, PDFs are used when the creator wants to share the document without alternation be recipients. However, you can find both online and offline editors if you need to alter a PDF document.

For example, PDF Candy has the online document editor. There, you can highlight or strike out text, add images or shapes, draw lines or whiteout content, etc.

PDF definition and how to edit it

How to Convert PDF files?

Should you require a PDF file to be in a different format, it is possible to convert them. For example, turn your PDF into DOCX or JPG. In addition, it's possible to save other files in PDF format: PPT, XLSX, ODT, etc.

Convert PDF

How to Protect PDF?

PDFs can be password protected so that only authorized people can open the files. You can do this in PDF Candy online by selecting the "Protect PDF" tool. After choosing this option, insert a secure combination and get your documents secured.

Protect PDF

What Else Can Be Done with PDF?

Working with PDF format

What Are the Benefits of PDF Format?

PDFs have remained popular as the major means of sharing documents. But why people are keen on it?

The key advantages include:

  • Cross-platform compatibility. PDFs can be viewed on virtually any device and operating system without compromising formatting. Whether you're using a computer, tablet, or smartphone, PDFs ensure consistent display across platforms.
  • Security features. PDFs offer robust security options, including password protection, encryption, watermark, and digital signatures, to safeguard sensitive information from unauthorized access or tampering. These features make PDFs ideal for sharing confidential documents securely.
  • Compression Capability. PDFs can be compressed without compromising quality, resulting in smaller sizes that are easy to share via email or upload/download from the internet.
  • Interactive elements. PDFs support a wide range of interactive elements such as hyperlinks, bookmarks, forms, and annotations. These features enhance the user experience and enable the creation of presentations, eBooks, and digital forms.
  • Printability. PDFs are optimized for printing, ensuring high-quality output on paper. They preserve the layout and design of the document, including fonts, images, and colors, making them ideal for producing professional-looking print materials.
  • Archival quality. PDFs are designed for the long-term preservation of digital documents. They encapsulate all necessary elements in a single file, including fonts and graphics. Hence, the document remains intact and accessible for years to come.
  • Accessibility. PDFs support accessibility features such as text-to-speech conversion, screen reader compatibility, and tagging for assistive technologies. This ensures that individuals with disabilities can access and interact with PDF documents effectively.

In summary, the PDF format offers a comprehensive set of features. This makes it an indispensable tool for creating, sharing, and preserving digital documents across various industries and applications. Its flexibility, reliability, and security make it the preferred choice for professionals and individuals alike.

How Does PDF Compare to Other Formats?

The PDF can be compared to various document formats, each with its characteristics and purposes. Here are some common formats that PDFs are often contrasted to:

Word Documents (DOCX)Like PDFs, Word format is widely used for creating and sharing text-based documents. However, while they are primarily used for word processing, PDFs are more suitable for preserving the layout and formatting of documents across different platforms.
JPEG/PNG ImagesJPEG and PNG images are commonly used for storing and sharing visual content such as photographs and graphics. While pictures are static and non-editable, PDFs can contain images along with text, hyperlinks, and other interactive elements, making them more versatile for document creation.
HTML (HyperText Markup Language)HTML is the standard markup language for creating web pages. While HTML is used for designing and displaying content on the web, PDFs can be seen as snapshots of online pages, providing a consistent representation of it for offline viewing and printing.
ePubePub is an eBook format designed for reflowable content, allowing readers to adjust font sizes and layouts to fit their preferences. ePub is ideal for reading on eBook readers and mobile devices. PDFs are more suitable for fixed-layout documents with precise formatting requirements, such as manuals and reports.
Excel Spreadsheets (XLSX)Excel spreadsheets are used for organizing and analyzing data in tabular format. While Excel files are optimized for numerical data and calculations, PDFs can be used to share static snapshots of spreadsheets, ensuring consistent presentation across different devices and software.
PowerPoint Presentations (PPT)PowerPoint presentations are used for creating visual slideshows for business, education, and other purposes. While these files are interactive and editable, PDFs can be utilized for presenting on a device without PowerPoint or for printing purposes.


What editing capabilities do PDF editors offer?

PDF editors offer a wide range of editing capabilities, including adding, deleting, and modifying text; annotating with comments, highlights, and drawings; inserting, deleting, and reordering pages; and converting PDFs to other file formats.

Can I edit a scanned PDF document?

Yes, you can edit a scanned PDF document by using Optical Character Recognition (OCR) technology, which converts scanned images into editable and searchable text. Many PDF editors offer built-in OCR functionality for this purpose.

Can I add or remove images from a PDF file?

Yes, you can add new images to a PDF document by inserting them from your computer or another source. Similarly, you can delete existing images from a PDF using the editing tools provided by PDF editors.

Edit a PDF document


In conclusion, PDF is a cornerstone of modern communication, offering unparalleled versatility and reliability. From its inception by Adobe Systems to its widespread adoption across industries and platforms, the PDF format has revolutionized the way we create, share, and preserve documents.

As an indispensable tool in our digital arsenal, the PDF continues to empower individuals and organizations worldwide. They ensure seamless access to information across diverse devices and environments.

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