PDF

PDF stands for Portable Document Format. It is a file format developed by Adobe Systems in the early 90s to facilitate document exchange. A PDF document will appear exactly the same regardless of computer or operating system. It can be created from any printable file using a PDF Creator and can be viewed on any computer or handheld device using a free PDF Reader. These qualities have made PDF the defacto standard for distributing electronic documents.

The idea of Portable Document Format was first stated by John Warnock, the co-founder of Adobe Systems, in his Camelot Project paper in 1991. He wrote in his project white paper about a technology to share and distribute documents which could be viewed on any computer and could be printed locally. This paper had led to the development of PDF utilizing Adobe’s already established postscript technology.

In 1992, Adobe released the first version of PDF, code-named “Carousel”, at Comdex which is an annual business technology event. PDF was recognized as the “Best of Comdex” in the event. In 1993, Adobe launched Acrobat which came with the tools to create and view PDF files. Adobe initially charged for both Acrobat and Acrobat Reader, but later it released Acrobat Reader as a free software.

In 1994, Adobe released Acrobat 2.0 which supported embedded multimedia content and links to external files. In the next year, Acrobat plug-in for Netscape Navigator was released which enabled PDF files to be viewed directly on the web browser. Eventually, PDF became the ideal format to share documents on the web.

Over the years, several features have been added to the Acrobat, including the tools to annotate, review & digitally sign PDF files. Along with each version of Acrobat, new versions of PDF had been published.

In May 2005, PDF got a major recognition when PDF/A (which is a subset of PDF based on PDF 1.4http://www.aiim.org/documents/standards/19005-1_FAQ.PDF) was approved by ISO as the standard format for long-term archiving and preserving electronic records.http://www.adobe.com/pdf/about/history/ In 2007, Adobe submitted the specifications of PDF 1.7 to the ISO to approve it as the open standard format for electronic documents. It was approved by ISO in July 2008 as ISO International Standard - ISO 32000-1.http://www.adobe.com/devnet/pdf/pdf_reference.html

A PDF Creator (or PDF Writer) is a software that allow users to create PDF files. PDF files can be created from virtually any file that can be printed, which includes MS Office files, images and CAD files. Some PDF creators can also convert a webpage or email into PDF. The following are two popular free PDF Creators.

1. CutePDF
2. PrimoPDF

A PDF Reader is a software that allow users to view and print PDF files. Adobe Reader is the most widely known PDF Reader which is available at free of cost for all major Operating Systems. There are also special versions of Adobe Reader that can be used in mobile devices. Foxit Reader is another PDF reader which is best known as an open-source alternative to Adobe Reader.

A PDF Editor is a software that allow users to edit PDF files. Using this tool, text and images in a PDF file can be edited on per-line basis. It also enables users to add watermark, insert hyperlink, whiteout & highlight, merge & split, encrypt & decrypt, etc. Adobe Acrobat and NitroPDF are two popular PDF Editors.

PDF Converters are used for converting PDF files into various files such as Word , Excel or JPEG. There are downloadable softwares as well as online converters. The following are some of the free online PDF converters.

1. Cometdocs
2. PDFtoWord
3. PDFtoExcelOnline