unlimited e-books for free

a book that is displayed on a computer screen or on an electronic device that is held in the hand, instead of being printed on paper

You can download unlimited e-books for free.
academic e-books in multiple electronic formats

The file may be read on a personal computer, a personal digital assistant, or on an electronic device designed specifically for reading e-books.
Books in digital format, also known as e-books, can be read on devices lacking the power and screen space to afford a regular Web browser.