plants cultivated by humans for food, fiber, and fuel
major categories: grain, legume, vegetables, fruits, oilseeds, roots
each crop species shaped by millennia of selective breeding
annual crops complete lifecycle in one season; perennials persist across years
yield depends on soil fertility, water availability, photosynthesis efficiency
cultivation practices: rotation, intercropping, cover cropping
genetic diversity preserved through seed banks
core output of agriculture, processed after harvest