Rowley Jefferson is a fictional character from the popular book series Diary of a Wimpy Kid, created by Jeff Kinney. He is best known as the best friend of the main character, Greg Heffley. Rowley is characterized by his cheerful personality and childlike innocence, often providing comic relief in the series. In the books, Rowley is depicted as a loyal friend who sometimes struggles to stand up for himself. He has his own spin-off series titled Rowley Jefferson's Awesome Friendly Adventure, which showcases his imaginative storytelling and adventures. Rowley's character adds depth to the themes of friendship and growing up in the series.