Modelling water with simple Mercedes-Benz models

The structures and properties of biomolecules, such as proteins, nucleic acids and membranes, depend on water. Water is also very important in industry. Overall, water is unusual substance with more than 70 anomalous properties. The understanding of water is advancing significantly due to theoretical and computational modelling. There are different kinds of models, models with fine-scale properties and increasing structural detail with increasing computational expense and simple models which focus on global properties of water like thermodynamics, phase diagram and are less computational expensive. Simplified models give a better understanding of water in ways that complement more complex models. Here, we review a simple model, the two-dimensional Mercedes-Benz model of water. We present results by Monte Carlo simulations for anomalies and phase diagram and application of various theoretical methods.