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.

An article is a written work published in a print or electronic medium. It may be for the purpose of propagating the news, research results, academic analysis or debate. wikipedia.org

A blog is a personal journal published on the World Wide Web consisting of discrete entries ("posts") typically displayed in reverse chronological order so the most recent post appears first. wikipedia.org

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

A newsletter is a regularly distributed publication generally about one main topic that is of interest to its subscribers.

Professional writing involves the use of clear language to convey information in a way that is easily understood by the intended audience. Individuals who can use language well may be employed as full-time professional writers in a variety of communications-related occupations, such as wikipedia.org

SEO content is any content created with the goal of attracting search engine traffic. wikipedia.org

Writing is a medium of communication that represents language through the inscription of signs and symbols. wikipedia.org