is any nonfiction narrative writing based on the author’s personal memories. The assertions made in the work are thus understood to be factual. While memoir has historically been defined as a subcategory of biography or autobiography since the late 20th century, the genre is differentiated in form, presenting a narrowed focus, usually a particular time phase in someone’s life or career. A biography or autobiography tells the story “Of a life”, while a memoir often tells the story of a particular career, event, or time, such as touchstone moments and turning points in the author’s life. The author of a memoir may be referred to as a memoirist or a memorialist.