Graham A. Nelson (born 1968) is a British mathematician, poet, and the creator of the Inform design system for creating interactive fiction (IF) games. He has also authored several IF games, the most important ones being Curses (1993) and Jigsaw (1995).
Nelson is the author of the Inform Designer's Manual, which includes one of the first published works of interactive fiction theory, an essay titled "The Craft of Adventure". He has also written several important essays on interactive fiction in the field.
Nelson studied at Selwyn College, Cambridge and Magdalen College, Oxford, before becoming a fellow in pure mathematics at St Anne's College, Oxford. He co-edited Oxford Poetry and in 1997 received an Eric Gregory Award from the Society of Authors for his poetry. As of 2004 he was managing editor of Legenda, the imprint of the Modern Humanities Research Association.