A memoir (US: /ˈmemwɑːr/; from French: mémoire: memoria, meaning memory or reminiscence) is a collection of memories that an individual writes about moments or events, both public or private, that took place in the subject's/person’s life. The assertions made in the work are 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. A biography or autobiography tells the story "of a life", while a memoir often tells a story "from a life", such as touchstone events and turning points from the author's life. The author of a memoir may be referred to as a memoirist or a memorialist.