National Dog Day was celebrated on Tuesday, with many celebrities tweeting out photos of their dogs.

National Dog Day

Founded by Colleen Paige in 2004, National Dog Day celebrates man’s best friend and was created to help raise awareness to stop puppy mills and encourage adopting dogs.

“I want this to be a day to encourage dog ownership of all breeds, mixed and pure – to help abolish puppy mills and end breed specific legislation so we can create a world where all dogs (and every animal) can live a happy, save and ‘abuse-free life,’” Paige states on the National Dog Day official website.

National Dog Day quickly took over Twitter, and many celebrities took part in the celebration, sharing photos of their dogs.