The primary purpose of ISO 19005 is to define a file format based on PDF, known as PDF/A, which provides a mechanism for representing electronic documents in a manner that preserves their static visual appearance over time, independent of the tools and systems used for creating, storing or rendering the files.
A secondary purpose of ISO 19005 is to define a framework for representing the logical structure and other semantic information of electronic documents within conforming files.
Another purpose of ISO 19005 is to provide a framework for recording the context and history of electronic documents in metadata within conforming files.
These goals are accomplished by identifying the set of PDF components that can be used, and restrictions on the form of their use, within conforming PDF/A files.
At present, there are three "parts" to the PDF/A family of standards:
Based on PDF 1.4, PDF/A-1 is the original PDF/A specification published in 2005.
Purchase PDF/A-1 from ISO's website. The corrigenda for PDF/A-1 may also be downloaded from the same page.
Based on PDF 1.7 (ISO 32000-1), PDF/A-2 extends the PDF/A concept to encompass the new features added to PDF between versions 1.4 and 1.7. PDF/A-2 requires that any attached file be either itself a PDF/A file or plain text.
Purchase PDF/A-2 from ISO's website.
PDF/A-3 is identical to PDF/A-2, but permits arbitrary attachments to PDF/A-3 files.
Purchase PDF/A-3 from ISO's website.