History and Standardization of PDF
– Adobe Systems released the PDF specification in 1993.
– PDF was initially popular in desktop publishing workflows.
– PDF competed with other formats such as DjVu, Envoy, and Common Ground Digital Paper.
– PDF became an open standard in 2008 and was published by the International Organization for Standardization (ISO).
– Adobe granted royalty-free rights for all patents necessary for PDF-compliant implementations.
– PDF was standardized as ISO 32000 in 2008.
– The latest edition, ISO 32000-2:2020, was published in December 2020.
– ISO 32000-2 does not include any proprietary technologies as normative references.
– The PDF Association made ISO 32000-2 available for free download in April 2023.
– The specification is controlled by an ISO Committee of volunteer industry experts.
Content of PDF Files
– A PDF file can contain text, graphics, and images.
– Content streams store typeset text.
– Vector graphics are used for illustrations and designs.
– Raster graphics are used for photographs and other images.
– PDF files can also include multimedia objects, links, forms, and JavaScript.
Technical Details of PDF
– PDF is based on the PostScript page description programming language.
– Fonts can be embedded or replaced in a PDF document.
– PDF supports plug-ins for handling embedded content.
– PDF documents can include forms and JavaScript.
– PDF combines vector graphics, text, and bitmap graphics.
Features of PDF
– PDF supports encryption and digital signatures.
– File attachments and metadata can be included in PDF files.
– PDF allows for logical structuring elements and annotations.
– Rich media, including video content, can be embedded in PDF.
– PDF can handle three-dimensional objects using U3D or PRC.
Miscellaneous
– Adobe granted royalty-free rights for all patents necessary for PDF-compliant implementations.
– The specification is controlled by an ISO Committee of volunteer industry experts.
Portable Document Format (PDF), standardized as ISO 32000, is a file format developed by Adobe in 1992 to present documents, including text formatting and images, in a manner independent of application software, hardware, and operating systems. Based on the PostScript language, each PDF file encapsulates a complete description of a fixed-layout flat document, including the text, fonts, vector graphics, raster images and other information needed to display it. PDF has its roots in "The Camelot Project" initiated by Adobe co-founder John Warnock in 1991. PDF was standardized as ISO 32000 in 2008. The last edition as ISO 32000-2:2020 was published in December 2020.
 Adobe PDF icon | |
| Filename extension | .pdf |
|---|---|
| Internet media type |
|
| Type code | PDF (including a single trailing space) |
| Uniform Type Identifier (UTI) | com.adobe.pdf |
| Magic number | %PDF |
| Developed by | Adobe Inc. (1991–2008) ISO (2008–) |
| Initial release | June 15, 1993 |
| Latest release | 2.0 |
| Extended to | PDF/A, PDF/E, PDF/UA, PDF/VT, PDF/X |
| Standard | ISO 32000-2 |
| Open format? | Yes |
| Website | iso |
PDF files may contain a variety of content besides flat text and graphics including logical structuring elements, interactive elements such as annotations and form-fields, layers, rich media (including video content), three-dimensional objects using U3D or PRC, and various other data formats. The PDF specification also provides for encryption and digital signatures, file attachments, and metadata to enable workflows requiring these features.
