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The mixtape "Best Day Ever" was released in 2011 by American rapper and record producer Mac Miller. It was Miller's first full-length project and showcased his talent as a lyricist and producer. The mixtape consists of 17 tracks and features guest appearances from artists such as Kendrick Lamar, Wiz Khalifa, and Curren$y. It combines elements of hip hop, rap, and R&B, showcasing Miller's versatility and creativity.