What Is PDF File

A PDF file is a short name for "Printable Digital Format". Usually, the file name contains extension of ".pdf" in lower case.

PDF file is different from other document file such as Microsoft Word, Microsoft Excel or Open Office Write because any content in the PDF file cannot be changed, modified or deleted. Otherwise, you need to have a password to change the content.

PDF files can be opened with Adobe Acrobat Reader made by Adobe. Use version 5.0 until version 9.0. You can download Adobe Acrobat Reader for free from Adobe website. When opened, you can view PDF file to read the content or print it out. But, it cant be modified.