quoted from:https://www.researchgate.net/publication/228753619_The_Channel-Hillslope_Integrated_Landscape_Development_Model_CHILD

The CHILD model simulates the evolution of a topographic surface and its subjacent stratigraphy under a set of driving erosion and sedimentation processes and with a prescribed set of initial and boundary conditions. Designed to serve as a computational framework for investigating a wide range of problems in catchment geomorphology, CHILD is both a model, in the sense that it comprises a set of hypotheses about how nature works, and a software tool, in the sense that it provides a simulation environment for exploring the consequences of different hypotheses, parameters, and boundary conditions. Here we will use the term model to refer collectively to the software and the assumptions and hypotheses embedded within it.