Rice has been cultivated in China since ancient times and was introduced to India before the time of the Greeks. Records of rice cultivation in China go back 4,000 years. In classical Chinese, the words for agriculture and for rice are synonymous, indicating that rice was already the staple crop at the time the language was taking form. In several Asian languages the words for rice and food are identical. Many ceremonies have arisen in connection with planting and harvesting rice, and the grain and the plant are traditional motifs in Oriental art. Thousands of rice varieties are now known, both cultivated and diminished, and the original form is unknown.