Why would I want an e-book if I have the print book?

Simplify.
You can have as many of Joel’s books as you want on one e-reader device. You can go

ebookbook
An e-reader device is lighter and more compact than a stack of books. You can have many books on one device. For example, you could have all of Joel’s books on your device as well as several versions of the Bible, making it simple and convenient to look up the Bible references in Joel’s books. Having books on an e-reader also saves wear and tear on your print books, especially while travelling.

Search.
You can use the search function on the e-reader and enter the word or phrase you are looking for in a book. The e-reader displays a list of all instances of that search term in the book. Selecting any item in the list takes you directly to that location in the book.

Highlight and make notes.
Just as with a print book, you can highlight passages and make notes in an e-book. Then you can view all your notes at once or search your notes for a particular word or phrase.  Most readers have several colors available for highlighting.

Adjust font size and brightness.
You can easily enlarge or reduce the type size and make the page brighter or dimmer. These are handy features when you want to read in dim lighting or need larger print.