Modelling refers to the act or process of creating a model, which is an accurate representation or interpretation of something. In other words, modelling involves using mathematical concepts and techniques to develop models that can help us understand real-world phenomena and make predictions about future events based on data analysis. Models are used in various fields such as economics, finance, engineering, environmental science, medicine, and social sciences, among others. The process of creating a model involves identifying patterns or relationships within the data, developing equations that describe these patterns, and using simulations to test the accuracy of the models.