What is PDF?
Planet PDF offers the definitive answer

"What is PDF?"

It's a question we receive quite regularly at Planet PDF, along with the related -- but different -- question "What is Acrobat?"

The latter one typically results from someone not grasping the difference between Adobe Acrobat (commercial software) and the Acrobat Reader (free PDF-viewing tool). In some cases, the confusion is nurtured by Adobe's variations in the product's naming scheme with each successive version upgrade. Acrobat Exchange here today (v.3), gone tomorrow (v.4).

So as the Acrobat misunderstandings have continued to be perpetuated at the product level, we're powerless to do more than keep explaining the life cycle to new users.

But we'll take a stab at offering our definitive answer to the first question. But it's not quite as clear-cut as you might think!

PDF Spoken Here - Choose Your Dialect

If you said that the acronym "PDF" stands for the "portable document format," you'd be right. At least in the right (Adobe Acrobat-aware) circles.

In some other circles, however, proclaiming your belief in PDF could at the very least cause people to stare and point; in the wrong circles, you might suddenly have a military situation on your hands.

We've pulled together the following list of alternative (and legitimate) meanings for the PDF acronym, hastily collected across the Web, to help move intelligently within these differing spheres of understanding.

  • Pair Distribution Function
  • Panamanian Defense Force
  • Parameter Definition File
  • Parkinson's Disease Foundation
  • Particle Distribution Function
  • Parton Distribution Function
  • Personnel Deployment Function
  • Pig Dog Farm
  • Planar Deformation Feature
  • Platform Data File
  • Point Detonating Fuze
  • Portable Data File
  • Postdoctoral Fellow
  • Postscript Document Format
  • Power Density Function
  • Power Distribution Frame
  • Precision Direction Finding
  • Process Flow Design
  • Pretty Damn Funny
  • Primary Direction of Fire
  • Principal Direction of Fire
  • Printer Description File
  • Probability Density Function
  • Probability Distribution Function
  • Procedure Definition File
  • Process Flow Design
  • Processor-Defined Function
  • Procurement Data File
  • Product Development & Fulfillment company
  • Program Data File
  • Program Data Form
  • Program Development Facility
  • Programmable Data Formatter
  • Pulsar Data File

Some of you may want to sign up for "PDF News" -- it'll help you stay stay informed on the latest on handmade soaps and knitting designs at Pig Dog Farm.

No PDF catalog available in PDF, sorry to report.

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