If you save a document as WWF file, it wont allow to print that document. The World Wildlife Fund is asking you to “Save as WWF, Save a Tree”. Technically WWF is same as PDF format with the print option is completely blocked. The aim of WWF behind developing new file format is to stop documents being printed out unnecessarily. They are expecting to create awareness about the use of a paper and it will affect on environment. WWF documents can be opened with most programs that can open PDFs.
The WWF is developed a small software package that will install a “SAVE AS WWF” option in the print menu. After installing it, you can just select this option Save as WWF, and the document will be saved as WWF document. Once the document is created with “.WWF” extension, you can just use it as PDF file, to share, send via messenger, send via email and what ever you can do with PDF.
You can download WWF software package from Save as WWF website and it is completely free. But this software is at present only available for Mac OS, And Windows version will be available very soon. Please use this WWF format, save a tree and save our environment.