As a generic term, an electronic book (variously:digital book or e-edition) is a book-publication in digital form, consisting of text, images, or both, readable on computers or other electronic devices. Commercially produced and sold e-books are usually intended to be read on dedicated e-readers.
However, almost any electronic device that features a controllable viewing screen, including computers, tablets and smartphones can also be used to read e-books. Nowadays, both print as well as e-book selling is moving to the web. For instance, in the United States of America more "books are published online than distributed in hard copy in book shops".
As well as print books. E-Books are easy to read online using a computer or a mobile device such as an tablet or smart phone. Many e-book databases include the option of searching for keywords or phrases within the book, and some have enhanced features such as animations, video and audio supplements, hyperlinks.
The main reasons that people are buying E-book are prices, comfort and selection process. Notwithstanding that most people appreciate higher regular "bricks & mortar" bookshops, "yet almost every single one of us is buying books online". Based on this information it is almost certain that the e-publishing will soon overtake traditional publishing.
Most e-books display as PDF files using Adobe. To read an e-book online, usually all you need is a computer with an Internet connection PDF viewing software an up-to-date web browser.