What is a PDF File ?

 This article explains what PDF files are, how to open them, how to convert them to another format, such as an image or an editable file for use in Word or Excel, and how to protect or remove the password.

What is a PDF File?

A file developed by Adobe with a .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, videos, and more.

You will often see product manuals, e-books, brochures, job applications, scans, brochures, and all sorts of other documents that are available in PDF format. Web pages can even be saved in their full format as a PDF file for future reference.

Since PDF files don't depend on the software used to create them, or on any specific operating system or hardware, they look the same no matter what device they're opened on.

How to Open a PDF File

Most people go straight to Adobe Acrobat Reader when they need to open a PDF file. Adobe created the PDF standard and their program is surely the most popular free PDF reader out there. It's perfectly fine to use, but we think it's a bit of a bloated program with a lot of features you may never need or want to use.

Most web browsers, like Chrome and Firefox, can open PDF files on their own. You may need a plugin or extension for this, but it's quite handy to have one that automatically opens when you click on a PDF link online. Another way to open it in a browser is with a dedicated web opener like this one at FreePDFOnline.com.

We recommend SumatraPDF, Slim PDF Reader, or MuPDF if you're looking for something with a bit more features; all three are free. 

How to Edit a PDF File

Adobe Acrobat is the most popular PDF editor, but Microsoft Word does the same thing. There are also other PDF editors like Foxit PDF Editor and Nitro PDF Pro among others.

PDFescape, DocHub, and PDF Buddy are some free online PDF editors that make filling out forms like the ones you sometimes see on an application or tax form really easy. Simply upload your PDF to the website to add things like images, text, signatures, links, and more, and then download it back to your computer as a PDF.

A similar online PDF editor called Fill is great if you just need to add a signature to the PDF file. It also supports inserting checkboxes, dates, and regular text, but you can't use it to edit existing text or just fill out forms.

Whether you want to extract part of a PDF file as your own, or split a PDF file into several different individual documents, there are several ways to achieve this.

How to Convert a PDF File

Most of the people who want to convert a PDF file to another format are interested in it so that they can edit the content of the PDF file. Converting a PDF file means that it is no longer a .PDF file and instead opens in a program that is not a PDF reader.

For example, if you convert a PDF file to a Microsoft Word file (DOC and DOCX), you can open the file not only in Word, but also in other document editing programs such as OpenOffice and LibreOffice. Using these types of programs to edit a converted PDF file is probably much more convenient than an unknown PDF editor.

If you 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, e-books, and Microsoft Word documents and export them as PDFs, allowing them to be opened in a PDF or e-book reader.

It can be saved or exported from a specific format to PDF with a free PDF creator. Some even function as PDF printers, allowing you to "print" virtually any file to a .PDF file. Actually, it's just an easy way to convert almost anything to PDF. 

Some of the programs in the links above can be used both ways, i.e. you can use them to convert PDF to different formats and create PDF. Caliber is another example of a free program that supports conversion to and from an eBook format.

In addition, many of the mentioned programs can also merge multiple PDFs into one, extract specific PDF pages, and only save the images from the PDF. PDF Merge Free and FreePDFOnline.com are online methods to quickly merge multiple PDF files into one; The latter supports more than a dozen other PDF-related features.

EasePDF is an example of an online PDF to Word converter that can save the file in DOCX format.

EasyPDF.com is another online PDF converter that supports saving the PDF in a variety of formats, making it compatible with Word, PowerPoint, Excel, or AutoCAD. You can also convert PDF pages to GIF or a single text file. PDF files can be uploaded from Dropbox, Google Drive, or your computer. CleverPDF is a similar alternative.

Another conversion you can do is PDF to PPTX. When you use PDFConverter.com to convert the document, each page of the PDF file is divided into separate slides that you can use in PowerPoint or any other presentation software that supports PPTX files.

How to Secure a PDF

Protecting a PDF file can include requiring a password to open it, preventing someone from printing the PDF file, copying its text, adding comments, pasting pages, and more.

Some of the PDF creators and converters linked above and others like PDFMate PDF Converter Free, PrimoPDF, FreePDF Creator, Soda PDF, and FoxyUtils are some of the many free apps that can change these kinds of security options.