Industrial is one of the three main types of zones in TheoTown, the others being Residential and Commercial. Industrial zones allow citizens to build factories and other industry buildings to work in. Industrial zones are 100 Theons per tile.
Farms are a special version of industrial zones which cost only 10 Theons per tile.
Harbors are a special version of industrial zones, employing more workers. These are 200 Theons per tile.