Celebrities across the country are paying tribute to the late Casey Kasem, who passed away Sunday at the age of 82.
Kasem's impact in the world of music and radio is undeniable. One of the best-known voices on radio for nearly four decades, Kasem was the legendary host of the iconic music countdown program American Top 40, and also provided the voice of Shaggy on the beloved animated series Scooby Doo.
American Idol host Ryan Seacrest took over for Kasem on American Top 40 in 2004, and Seacrest was one of the first to tweet out his kind words for Casey after his passing.
Here are some of the many, many messages sent out by stars commemorating the life and memory of Casey Kasem.