How do we create an Earth-like model, capturing its inner-workings, from geophysical data? And more importantly, how much can we trust these models? This module explores these topics through geophysical inversion and data modelling. You will learn the fundamental concepts of making models fit data, signal processing, and the use of machine learning in Earth Sciences. You will move from simply running modelling software to understanding how it works, and the limitations of its outputs. This will equip you to critically test geological hypotheses and handle uncertainty in research and professional contexts.