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

English is a West Germanic language that was first spoken in early medieval England and is now a global lingua franca. wikipedia.org

Developmental editing is a form of writing support that comes into play before or during the production of a publishable manuscript, especially in the area of non-fiction writing. wikipedia.org

Copywriting is the use of words and ideas to promote a person, business, opinion or idea. wikipedia.org

Article spinning is a search engine optimization technique by which blog or website owners post a unique version of relevant content on their sites. It works by rewriting existing articles, or parts of articles, and replacing elements to provide a slightly different perspective on the topic. wikipedia.org

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

Proofreading (also proof-reading) is the reading of a galley proof or computer monitor to detect and correct production-errors of text or art. Proofreaders are expected to be consistently accurate by default because they occupy the last stage of typographic production before publication. wikipedia.org

An electronic book is a book-length publication in digital form, consisting of text, images, or both, readable on computers or other electronic devices. wikipedia.org