For those E-books purchased at Amazon you will need to use the Amazon Kindle reader.
For others you might download here you can obtain free reader software for your computer or mobile device.
Windows Users:
Mac Users:
- Blue Fire Reader
- Calibre
- iBooks - Download free from the Mac App Store
iOS Users:
- iBooks - Download free from the App Store
- Google Play Books
Android Users:
Windows and Mac users may also download Adobe Digital Editions for an excellent PDF reader system or just use any PDF reader such as Adobe Reader or even Preview on the Mac.