Alexander Calder is credited with inventing what type of sculpture?

Alexander Calder is widely regarded as the inventor of the mobile, a type of sculpture that is suspended in space and usually contains moving parts that sway and rotate when exposed to air currents or other forces. Calder pioneered the art form in the early 20th century, and his mobiles have profoundly impacted the development of modern and contemporary sculpture. They are known for their kinetic nature, playful designs, and ability to capture and express movement in unique and captivating ways.