Farming can be viewed as a system with inputs, processes, outputs, and feedback. Physical inputs include water, land, and raw materials while human inputs are money, labor, and skills. Processes transform inputs into outputs, which can be positive like crops and meat or negative like waste. Feedback puts money and knowledge back into the system. There are different types of farming like arable, pastoral, and mixed, which can be commercial, subsistence, or plantations. Sustainable agriculture maximizes yields through techniques like crop rotation, irrigation, and limited chemicals. The Green Revolution increased food production but was expensive, water intensive, and relied heavily on chemicals, negatively impacting the environment and farmers.