The document discusses how cartoons have become more mature and serious over time. It provides a brief history of animation from the early 1900s to present day. Theories for why cartoons are now tackling darker topics include creators wanting to address issues they care about and studios being more accepting of topics like violence and LGBTQ representation. Interviews with creators of shows like Steven Universe, Gravity Falls, and OK K.O.! suggest they did not view their shows as only for children and wanted to communicate meaningful ideas and stories through their work. While networks have influenced some content changes, creators often convince executives to approve their vision.