The study used a computer model to predict how cities might grow in the future. They focused on Thessaloniki in Greece, where the city has been spreading out more. The model looked at different factors like population and environment to make its predictions. They found that if things continue as they are, the city will keep spreading out into farmland and natural areas. But if rules are put in place to limit building in these areas, the city could grow more compactly within its current boundaries.