PDF or portable document format files are a file format that allows you to replicate a particular page, retaining the entire formatting and design.

While HTML design is getting to the point where you can recreate any newsletter, brochure or other document design pretty accurately, there are times when maintaining the full integrity of the document is important, so you'll want to turn the original file into a PDF file.

Your original file can be a Word file, Excel file or any other file, and you'll need to either purchase the Adobe Acrobat software at your favorite software store or Web site, or you can actually have Adobe convert your file for you. If you're working with sophisticated illustration, layout or graphic programs, such as Illustrator, Quark or Photoshop, you can obtain plug-ins or small software add-ons that can help you directly convert files made in those programs into PDF files.

To be able to read the PDF file, your visitors will need the Adobe Reader software on their computer, which is available for free at the Adobe site. For their convenience, you may want to include a link to Adobe on your site next to the links to your PDF files so they can download the reader if they don't already have it.

Aliza Sherman is an entrepreneur and author of Cybergrrl: A Woman's Guide to the World Wide Web (Ballantine Books). She is currently working on her next book and new company.