Amazon Kindle Fire e-book reader. (Image: kodomut, via Flickr / CC)

Not only are e-books becoming more and more popular; apparently, they also serve as an effective encouragement for reading among adult Americans.
According to a new research from the Pew Internet and American Life Project, “one-fifth of American adults (21%) report that they have read an e-book in the past year”.
Accordingly, if the age bracket broadened to over 16 years old for Americans who have used an electronic …