"The Black Album," officially titled "Metallica", is the fifth studio album by the American heavy metal band Metallica, released on August 12, 1991. It features a more mainstream sound compared to their earlier work, incorporating elements of hard rock. The album includes hit singles like "Enter Sandman" and "The Unforgiven," which contributed to its widespread popularity. The album was produced by Bob Rock and marked a significant turning point in Metallica's career, leading to increased commercial success. It has since sold over 16 million copies in the United States alone, making it one of the best-selling albums in history.