it depends if is a book of a journal, look on one of the first pages, it should have something like a copyright page or whatever, but it should say something like fiction or non fiction. if it is a journal you write yourself, if you make up a character but base the story on a true event, it is historical non fiction. if it is something that actually happened, it is non fiction.
Fiction and nonfiction.
(Apex) Prose can be used in fiction and nonfiction writing.
The subgenres of prose are too numerous to list, as prose is, essentially, anything that is not poetry. All types of Fiction, nonfiction, and oftentimes drama can all be classified as prose.
Nonfiction prose is non-poetic writing about real people and events. A good example of this type of writing would be historical accounts of war.
An article is a nonfiction prose composition that is part of a magazine or newspaper and typically focuses on a single topic, providing information or analysis to the readers.
Article,
a form of nonfiction prose in which the author writes about his or her own life
Fred B. Myers has written: 'The range of literature: nonfiction prose' -- subject(s): English prose literature, Readers
also nonfiction, of prose writing or books, "telling of facts, real events, and real people," 1866, a librarians' word, first in the reports of the Bo
Argumentive essay
Creative nonfiction.
The main types of literary form include poetry, prose, drama, and nonfiction. Poetry is characterized by meter and rhythm; prose is ordinary written language distinguished from verse; drama is a form of literature intended to be performed by actors; and nonfiction is writing based on facts and real events.