On multi-rogue wave solutions of the NLS equation and positon solutions of the KdV equation

We discuss multi-Peregrine breather solutions to the nonlinear Schrodinger equations which are relevant in the description of rogue waves in hydrodynamics or in nonlinear optics. We also describe some basic properties of multi-positon and positon-soliton solutions to the Korteweg-de Vries equations and speculate about their possible links with freak waves.