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What is a PDF File?

How to Open, Edit, & Convert PDF Files



Question: What is a PDF File?

Did you find a PDF file on your computer and wonder what program should open it? Maybe someone emailed you a PDF file but you're not sure how to use it. Perhaps you tried to open the PDF file but Windows told you that it could not open it.

Before you can open a PDF file you'll need to determine what kind of file the .PDF file extension refers to.

Answer: A file with the PDF file extension is a Portable Document Format file.

Other types of files may also use the PDF file extension, though considering the popularity of the Portable Document Format this is unlikely. If you know of any additional file formats that use the .PDF extension, please let me know so I can update this information.

How To Open a PDF File

The easiest way to open a PDF file is to double-click on it and let your PC decide which default application should open the file. If no program opens the PDF file then you probably don't have an application installed that can view and/or edit PDF files.

Chances are, however, Adobe Reader or another PDF reader program will open the PDF file. Adobe Reader, and most other PDF readers, are free downloads.

Programs like the already mentioned Adobe Reader will open PDF files, as will free programs like SumatraPDF, Nuance PDF Reader, and many more. See this list of free PDF readers for more options.

Adobe Acrobat is the most popular PDF editor but Microsoft Word 2013 will do it too. Other PDF editors also exist, like Foxit Advanced PDF Editor and Nitro Pro, among others.

Some free programs also exist that will create PDF files from pretty much any document you have. See this list of free PDF creators for more on some of those tools.

If you know of any more programs that open or edit PDF files, please send me a quick email and let me know the name of the program so I can update this page.

If you find that an application on your PC does try to open the PDF file but it's the wrong application or if you would rather have another installed program open PDF files, see my How To Change the Default Program for a Specific File Extension guide for making that change in Windows.

How To Convert a PDF File

There are three main ways to attempt to convert a PDF file to another file type:

  • Open the PDF file in its default program and choose to save the open file as another file format.
  • Use a Free PDF to Word Converter to convert the PDF file to a Microsoft Word compatible format, making it easy to edit, unlike the original PDF file.
  • Use Calibre (to convert to and from an eBook format) or a different File Conversion Online Service or Software Program to convert the PDF file to some other file format.

The first option involving opening the PDF file in its native program is preferable because it's both easier and will probably result in a more accurate file conversion. The PDF editors I already mentioned are good examples of programs that will do this.

Most people interested in converting a PDF file to some sort of format are interested in doing that so they can edit the PDF in a more familiar format. The second option above, using a PDF to Word converter, is a great choice because MS Word formats, like DOCX, can be opened and edited in a wide array of free and popular programs.

Of course if you don't have a program that opens and allows the saving of PDF files, and your PDF conversion needs are for some reason other than editing, a third-party file conversion tool (the third option) could be very useful.

Important: You cannot change the PDF file extension to one that your computer recognizes and expect the newly renamed file to be usable. An actual file format conversion using one of the methods described above must take place.

Still Having Problems Opening or Using a PDF File?

See Get More Help for information about contacting me on social networks or via email, posting on tech support forums, and more. Let me know what kinds of problems you're having with opening or using the PDF file and I'll see what I can do to help.

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