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File extension description in German
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File Extension PDF

Files with the file extension PDF originate from a universal file format which was developed by Adobe. PDF stands for Portable Document Format and is a format that is created independently of any type of platform. This makes the document viewable by any operating system or computing platform. This format is also very compact, which makes it easy to download or to transmit over the Internet via an email attachment.

A PDF document can contain images and hyperlinks in addition to text without having to use HTML (Hypertext Markup Language) to view it on the web. Instead, the format is based on a variant of PostScript which is a page language developed by Adobe that contains images, hyperlinks, text, and font styles in a single file. PostScript is a programming language which defines how a page can be printed or displayed on the screen.

How to Open PDF Files

Since PDF files are independent and unrelated to any type of operating system such as Linux, Windows, or Mac OS X, the files can be easily opened with Adobe Reader which typically comes preinstalled with most operating systems or by using a PDF viewer plugin in conjunction with your web browser.

If you do not have a PDF Viewer or Adobe Reader installed, you can obtain the programs from the Adobe website at The applications are free to download and will help you easily open and view documents with the PDF file extension.

Editing and Modifying PDF Files

When you use Adobe Reader or a PDF Viewer to open and read files with the PDF extension, you will be unable to edit or modify the document. In order to work with a PDF document, it is necessary to use a program such as Adobe Acrobat which helps you create and edit PDF files. The other option is to use a file converter to change the PDF file to a document file such as .DOC or .DOCX, perform the necessary modifications to the document, and then convert the file back to PDF using the same program.

There are a number of file converters online that allow you to perform conversions, so you can edit the document. You can also create your own PDF files using a PDF creation program or, if you have the latest version of Microsoft Word, you can take a document that contains the .DOCX extension and simply click on File and then Save As to save the document in PDF format.

There are also a number of free PDF file viewing editing and programs online. If you Google the topic, you will find a variety of different applications which will help you accomplish these tasks.