Demand modeling is a way of predicting how many people are likely to buy something or use a service. It helps businesses plan for their future needs by figuring out how much of a product to produce and how many people will be using the services the company provides. To do this, businesses use data from many sources including information about past sales, customer trends, current supply and demand, and economic factors. By looking at all this information, companies can make more accurate predictions about future demand and plan more effectively.