American Top 40

American Top 40 (AT40) is a popular radio program that counts down the top 40 songs in the United States, based on their chart performance and radio airplay. Created by disc jockey Casey Kasem in 1970, it showcases current hits across various genres, making it a key source for music trends. The show typically includes commentary about the songs and artists, as well as trivia. AT40 has influenced music culture and remains a significant platform for discovering new music, evolving over decades with changes in broadcasting and chart methodologies.