Civilization began with agriculture. When our nomadic ancestors began to settle and grow their own food, human society was forever changed. Communities, no matter how sophisticated, cannot ignore the importance of agriculture, since to be far from dependable sources of food is to risk malnutrition and starvation. The global and interdependent nature of human society makes us fundamentally dependent on agriculture. In modern times, increasing amounts of food are needed to sustain our increasing population. Increased production must come from new technologies for the growing, transportation, and storage of food. Farm machinery and components used for large and small scale irrigation, seeding and cultivation, fertilization, harvesting, and food storage must be robust, dependable, and designed to work largely outdoors. Electrical components must withstand moisture, corrosive chemicals, and variable weather conditions. Center pivot irrigation requires the transfer of power and control signals from the stationary source to the rotating mechanism. Other types of rotating electrical machines perform jobs such as grain stirring and drying, moving grain in and out of storage, and enhancing dairy production through the use of rotary milking carousels. Mobile greenhouse  irrigation systems require  cable and hose management.