Short answers, pulled from the story.
Quirino Cristiani created the world's first animated feature film El Apóstol in 1917. This Italian-Argentine cartoonist utilized cutout animation techniques to move paper figures across a flat surface for political stories.
Lotte Reiniger produced Die Abenteuer des Prinzen Achmed in 1926 using silhouette styles drawn from traditional shadow play traditions found in Indonesia and France. She studied the history of ombres chinoises which had been popular in Europe throughout the 18th and 19th centuries.
Animators cut characters from paper, card, stiff fabric or photographs to create movement. Joints formed with rivets or pins allowed specific fixed motions within the frame while some films used backlit animation where light sources came from below the table.
Modern software replaced physical paper with vector graphics and scanned images today. The team behind South Park switched from actual construction paper to PowerAnimator and eventually Maya software for production after 1997.
Terry Gilliam directed Monty Python's Flying Circus animations beginning in 1969 and continuing until 1975. He often directed light coming from above his subjects instead of using backlit techniques common in other cutout styles.