Industry is one of the two main business categories. It is divided into Food Industry, Heavy Industry, Manufacturing, and High Tech, with the latter three divided into Low, Medium, High density, and Exceptional. Exceptional includes special buildings that work to increase the efficiency and profitability of it's corresponding lot.
Food Industries work differently to most other lots. It must be built in designated agricultural areas on certain maps, and works by defining an area where the farm will go. All types of farm function exactly the same, only differing in aesthetics. Silos can be built after every ten farms, which creates a circle of influence, increase the profit of each farm. Fertilizers further the increase even more, and can be built after every five silos, meaning fifty farms.
Heavy Industry are the starting industries the player can work with. They are the easiest to build requiring only unskilled workers in low densities. However, they are also the greatest polluters, which must be kept away from the wealthy Executives and Elites, and also other lots that depend on an environmental rating such as offices and High-Tech.
Manufacturing is the next step in industry development. They begin hiring skilled workers in their labor-force, produces slightly more in profit than Heavy Industry, and less pollution. However, unless you import Heavy industry, it is not meant to be a replacement for heavy industry, as it depends on it as a bought resource.
High Tech is the last step in industry development, hiring executives and elites to run their company. It produces the most profit and has a zero pollution ratio. It is also very intolerant of pollution, meaning it should be built in either a specialized "clean" city or kept some distance away from pollution sources. It uses a large amount of resources and buys in manufacturing as a resource.