When plants of the same kind are grown and cultivated at one place on a a large scale is called as a crop. Crops are classified on the basis of the seasons: Kharif and Rabi crops.

Kharif crops (Monsoon crops): The crops which are grown during the monsoon (rainy season) are called kharif crops. Seeds of the se crops are sown in the beginning of the monsoon season. After maturation, these crops are harvested at the end of the monsoon season (Oct-Nov).
Example: Paddy, maize, millet and cotton crops
Rabi crops (Winter crops): Crops which are grown during the winter season(October-March) are called Rabi crops. Seeds of these crops are sown in the beginning of the winter season. After maturation of crops, they are harvested at the end of the winter season (April- May).
Example: Wheat, Gram and Mustard.