The Kardar-Parisi-Zhang (KPZ) universality class describes stochastic interface growth with nonlinear terms. The Eden model — random cluster growth on a lattice — belongs to KPZ. Surface width scales as W ~ t^β with β = 1/3 in 1+1D, and correlation length grows as ξ ~ t^(1/z) with dynamic exponent z = 3/2.