Most of my books are also issued in a Portable Document Format. The Portable Document Format (PDF) (redundantly: PDF format) is a file format developed by Adobe in the 1990s to present documents, including text formatting and images, in a manner independent of application software, hardware, and operating systems.
This PDF format can either be read on your computer or printed out for spiral binding.
PDF’s are NOT designed to be displayed on an ebook reader. A PDF is an electronic representation of a printed book. An eBook’s main purpose is to be read on an eReader. A PDF will look exactly the same as the paper-and-ink copy of the book.