While synthetic organic polymers and polymer networks existed before Hermann Staudinger put forward his Macromolecular Hypothesis in 1920, both of these polymeric materials saw tremendous development and expansion after this Hypothesis, and, sometimes, because of it. This article overviews in tutorial style the history, chemistry, properties, uses, and economics of synthetic organic polymer networks, illustrating their occurrence in everyday life, and also summarizing recent important developments in the field. Polymer 215 (2021) 123322.