Aspects topologiques de la physique en basse dimension. Topological aspects of low dimensional systems : Session LXIX. 7 31 July 1998 The book contains the worked out lecture notes of the courses delivered at the summer school in Les Houches. They address graduate students and are of interest for researchers as well. The book can be used as an introduction into three closely related fields: anyons and fractional statistics fractional quantum Hall effect and knot theory. The theoretical papers are occasionally completed by reports on experimental techniques and besides of physics some application to biological systems can be found