Electronic book, commonly referred to as e-book, is a digital version of a printed book. Currently, there are many synonyms for the term e-book that people use interchangeably. One of the most popular alternatives is the term digital book, which refers to a book in a digital format that can be accessed via a computer or mobile device. Another synonym that is commonly used is the term e-reader, which is a device designed specifically for reading digital books. Additionally, some people use the term digital novel or e-textbook to describe electronic books that are intended for recreational or educational purposes, respectively. Other less popular synonyms for electronic book include cyber-book and virtual book.