Mathematics is the study of topics such as quantity, structure, space, and change. There is a range of views among mathematicians and philosophers as to the exact scope and definition of mathematics. wikipedia.org

Mathematics is the abstract study of topics encompassing quantity, structure, space, change, and other properties. wikipedia.org

An electronic book (variously, e-book, ebook, digital book) is a book-length publication in digital form, consisting of text, images, or both, and produced on, published through, and readable on computers or other electronic devices.

Fiction writing is the composition of not factual texts. Fictional writing often is produced as a story meant to entertain or convey an author's point of view.