 There are two main variants of SLE, "chordal SLE" which gives a family of random curves from two fixed boundary points, and "radial SLE", which gives a family of random curves from a fixed boundary point to a fixed interior point.These curves are defined to satisfy conformal invariance and a domain Markov property.It was discovered by as a conjectured scaling limit of the planar uniform spanning tree (UST) and the planar loop-erased random walk (LERW) probabilistic processes, and developed by him together with Greg Lawler and Wendelin Werner in a series of joint papers.