Paper, a thin sheet of matted cellulose fibers, traces its origins to East Asia, with archaeological evidence pointing to precursors in China as early as the 2nd century BCE. The standardized papermaking process is traditionally credited to the Han court eunuch Cai Lun around 105 CE. While the word "paper" derives from "papyrus"—an ancient Egyptian writing material—they are distinct technologies, with paper involving macerated fibers rather than laminated plant pith. By the 13th century, papermaking knowledge had spread from the Middle East to medieval Europe, leading to the establishment of water-powered paper mills. The 19th century revolutionized production; the independent development of wood pulping by Charles Fenerty and Friedrich Gottlob Keller in 1844 drastically reduced costs, establishing wood pulp paper as the dominant type globally.