Ebook (or e-book) is an abbreviation of the English termelectronic book and means book in digital format. It can be an electronic version of a book that has already been printed or just released in digital format.
Some of the most popular digital formats are HTML, PDF (Portable Document Format), ePub (electronic publication) and DjVu (pronounced deja vu). An ebook can be read through a computer, PDA, iPad, Smartphone or a device available for this purpose on the market called eBook Reader.
The eBook Reader (eReader), such as the Amazon Kindle, is a portable device created specifically for reading digital books. It has a screen lighting technology different from other digital readers, allowing the reader to feel closer to reading the paper book.
You can get ebooks for free from online public libraries or other sites that offer digital books, such as Google Books. Ebooks can also be purchased from various online sales sites.