Michel de Montaigne was a French Renaissance philosopher and writer who popularized the essay as a literary genre. His most famous work, "Essais" (Essays), is a collection of personal reflections on a wide range of topics, characterized by its merging of casual anecdotes and autobiography with intellectual insights. Montaigne's writing style was innovative for its time, emphasizing self-exploration, skepticism, and a conversational tone that continues to influence literature and philosophy today.