A cassette is a small, rectangular container that holds magnetic tape used for recording and playing audio. It was popular from the 1970s to the 1990s, allowing users to listen to music and record sounds. Cassettes typically have two reels inside, which move the tape past a playback head in a cassette player. Cassettes were widely used before the rise of digital music formats like CDs and MP3s. They offered a portable way to enjoy music and were often used to create mixtapes. Although less common today, cassettes have seen a resurgence among collectors and enthusiasts.