The document discusses different types of cropping systems, including mono cropping, multiple cropping, intercropping, sequence/relay cropping, crop rotation, and mixed cropping. It provides examples of multiple cropping, where two or more crops are grown consecutively in the same field in a year, and relay cropping, where wheat is harvested with little disturbance to the growing soybean crop. The document notes that using different cropping systems reduces risks and provides insurance against the failure of one crop.