How Does iPad Differ from Other E-readers?
An e-reader is any electronic device that enables you to download and read books, magazines, PDF files, or newspapers, as well as documents such as manuals or reports. These devices are portable and typically dedicated only to reading electronic content. Most use E Ink technology to create a paper-like reading experience.
The iPad is a bit different: As you know, it isn't used for only reading books, and you have to download an app to enable it as an e-reader (though just about every e-reader app made for the iPad is free). Also, iPad doesn't offer the paper-like reading experience — you read from a computer screen (though you can adjust the brightness of the screen and change its background color).
When you buy a book or magazine online (or get one of many free publications), it downloads to your iPad in a few seconds using your Wi-Fi or 3G/4G connection. After you have your e-reader app and some content, iPad offers several navigation tools to move around a book, all of which you explore in this chapter.
iBooks 2 introduced tools for reading and interacting with book content and was targeted primarily at the textbook market. You can even create and publish your own interactive textbooks using a Mac app called iBooks Author.