.PDF File Extension

Cross-platform document created by Adobe Acrobat or a program with the Acrobat plug-in; commonly used for e-mail attachments or for saving publications in a standard format for viewing on multiple computers; usually created from another document instead of from scratch.

PDF files may contain text, images, forms, annotations, outlines, and other data. They preserve fonts and formatting electronically across multiple platforms and appear the same on the screen as they will when printed on paper. Google, Bing, and other search engines now index PDF documents, which can be viewed in a Web browser using the free Adobe Reader plug-in.

PDFs can also be created in Mac OS X by selecting "Print..." from an application's File menu. Then instead of clicking "Print," choose "Save as PDF" from the PDF drop-down menu in the lower-left corner of the window.

PDF files can be created and edited with Adobe Acrobat, a commercial program. They can be opened and viewed using the free Adobe Reader or the Adobe Reader plug-in, which is available for most Web browsers.

View the PDF definition for more information.