A memoir does more than “retell a story” that really happened. A memoir investigates into a personal event that took place in the past. From the Purdue OWL:
Difference Between the Personal Essay and the Memoir
From the resource:
While the personal essay can be about something that is current and still unfolding, the memoir tends to discuss past events. Memoir is similar to the personal essay, except that the memoir tends to focus more on life-changing events or person. Where the personal essay explores, free from any need to interpret, the memoir interprets, analyzes, and seeks the deeper meaning beneath the surface experience of particular events.
The memoir continually asks the following questions:
- Why was this event of particular significance?
- What did it mean?
- Why is it important?
In this sense, the memoir is heavier than the personal essay, and it mines the past to shed light on the present. The memoir seeks to make sense of an individual life.