Artist trading cards, also known as ATCs, are small cards that are highly collectible due to their unique and artistic nature. There are various other names for artist trading cards, including art cards, mini masterpieces, pocket art, and artist trading editions. These cards usually measure 2.5 x 3.5 inches, making them an ideal size for quick, creative expressions of art. People collect and trade them all over the world. ATCs can be made using a wide variety of materials and techniques, from mixed media to watercolor. Whatever they are called, artist trading cards continue to be a popular and fun way for artists to express themselves and connect with others in the community.