PDF File Format Version number:
Portable Document Format (PDF) is an open file format created by Adobe Systems in 1993 and is also published as the ISO 32000-1:2008 standard as of July 1, 2008. It is used for representing 2D (and in more recent versions 3D) documents in a device independent and resolution independent fixed-layout document format. Each PDF file encapsulates a complete description of a 2D document (and, with the advent of Acrobat® 3D, embedded 3D documents) that includes the text, fonts, images, and 2D vector graphics that compose the document.
Different PDF standards
- PDF/X for the printing and graphic arts as ISO 15929 and 15930 (working in ISO TC130)
- for archiving in corporate/government/library/etc environments as ISO 19005-1:2005 (work done in ISO TC171)
- PDF/E for exchange of engineering drawings as ISO 24517-1:2008 (work done in ISO TC171)
- PDF/UA for universally accessible PDF files used to ensure accessibility by users who are impaired in some way.
Table of PDF version changes:
|Version||Year of publication||Significant new features|
|1.4||2001||JBIG2, transparency, OCR text layer|
|1.5||2003||JPEG2000, linked multimedia|
|1.6||2004||Embedded multimedia, XML forms, AES encryption|
What is the PDF/A document specification?
The PDF/A standard is not a specific PDF version. It is a subset of PDF features. It does not define an archiving strategy or the goals of an archiving system but identifies a "profile" for electronic documents that ensures the documents can be reproduced the exact same way in years to come. A key element to this reproducibility is the requirement for PDF/A documents to be 100 % self-contained. All of the information necessary for displaying the document in the same manner every time is embedded in the file. This includes, but is not limited to, all content (text, raster images and vector graphics), fonts, and color information. A PDF/A document is not permitted to be reliant on information from external sources (e.g. font programs and hyperlinks).
- Audio and video content are not supported.
- All fonts must be embedded and also must be embedded legally for unlimited, universal rendering.
- Color spaces specified in a device-independent manner.
- Encryption is disallowed.
- Use of standards-based metadata is mandated.