A modeller is a person who creates or constructs models, which are representations or replicas of something. These can be physical objects such as buildings, vehicles, or sculptures; or they can be abstract concepts like mathematical equations or computer simulations. Modellers use various tools and techniques to create their models, depending on the nature of what they're modelling. In fields such as science, engineering, and architecture, a modeller is often an expert who uses data analysis, research, and other methods to develop accurate representations of complex systems or phenomena.