What is a PDF File?

How to open, edit, & convert PDF files

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Developed by Adobe Systems, a file with the .PDF file extension is a Portable Document Format file.

PDF files can contain not only images and text, but also interactive buttons, hyperlinks, embedded fonts, video, and more. 

You'll often see product manuals, eBooks, flyers, job applications, scanned documents, brochures, and all sorts of other documents available in the PDF format.

Because PDFs don't rely on the software that created them, nor on any particular operating system or hardware, they look the same no matter what device they're opened on.

How To Open a PDF File

Most people head right to Adobe Acrobat Reader when they need to open a PDF. Adobe created the PDF standard and its program is certainly the most popular PDF reader out there. It's completely fine to use it, but I find it to be a somewhat bloated program with lots of features that you may never need or want to use.

Most web browsers, like both Chrome and Firefox, can open PDFs themselves. You may or may not need an add-on or extension to do it, but it's pretty handy to have one open automatically when you click a PDF link online.

I highly recommend SumatraPDF or MuPDF if you're after something a bit more. Both are free.

How To Edit a PDF File

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

FormSwift's Free PDF Editor, PDFescapeDocHub, and PDF Buddy are a few free-to-use online PDF editors that make it really easy to fill out forms, like ones you sometimes see on a job application or a tax form.

Just upload your PDF to the website to do things like insert images, text, signatures, links, and more, and then download it back to your computer as a PDF.

See our Best Free PDF Editors list for a regularly updated collection of PDF editors if you're after something more than just form filling, like adding or removing text or images from your PDF.

How To Convert a PDF File

Most people wanting to convert a PDF file to some other format are interested in doing that so they can edit the contents of the PDF. Converting a PDF means that it will no longer be a .PDF, and instead will open in a program other than a PDF reader.

For example, converting a PDF to a Microsoft Word file (DOC and DOCX) lets you open the file not only in Word, but also in other document editing programs like OpenOffice and LibreOffice. Using these types of programs to edit a converted PDF is probably a much more comfortable thing to do, compared to an unfamiliar PDF editor, like one of the programs I mentioned above.

If you instead want a non-PDF file to be a .PDF file, you can use a PDF creator. These types of tools can take things like images, eBooks, and Microsoft Word documents, and export them as PDF, which enables them to be opened in a PDF or eBook reader.

Saving or exporting from some format to PDF can be accomplished using a free PDF creator. Some even serve as a PDF printer, allowing you to virtually "print" pretty much any file to a .PDF file. In reality, it's just a simple way to convert pretty much anything to PDF. See How to Print to PDF for a full look at those options.

Some of the programs from the links above can be used in both ways, meaning you can use them to both convert PDFs to different formats as well as to create PDFs. Calibre is another example of a free program that supports converting to and from an eBook format.

Also, many of the programs mentioned can also merge multiple PDFs into one, extract out specific PDF pages, and save just the images from the PDF.

See these Free File Conversion Programs and Online Services for other ways to convert a PDF file to some other file format, including image formats, HTML, SWF, MOBI, PDB, EPUB, TXT, and others.

How to Secure a PDF

Securing a PDF may include requiring a password to open it, as well as preventing someone from printing the PDF, copying its text, adding comments, inserting pages, and other things.

PDFProtect!, FoxyUtils, and some of the PDF creators and converters linked to from above - like PDFMate PDF Converter Free, PrimoPDF, and FreePDF Creator - are just some free applications out of many that can change these types of security options.

How To Crack a PDF Password or Unlock a PDF

Though protecting a PDF file with a password is recommended in some circumstances, you may end up forgetting what the password is, disabling access to your own file.

If you need to remove or recover the PDF owner password (the one that restricts certain activities) or PDF user password (the one that restricts opening) on a PDF file, use one of these Free PDF Password Remover Tools.

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.