Lettuce is an annual or biennial herb of the genus Lettuce in Compositae. It is a very common edible vegetable. People in China, Japan and other countries often eat it after cooking. In western culture, people often eat it raw in salads, hamburgers and other foods. In Hong Kong, lettuce is also called Tang lettuce in order to distinguish it from western lettuce.

Lettuce can be divided into two categories: leaf lettuce, also known as lettuce, stem lettuce, also known as lettuce and fragrant bamboo shoots. Lettuce has many names, and it is called "thousand daughters' dish", "lettuce" and "borage" in this cursive script. Lettuce for stems is also called lettuce and fragrant bamboo shoots. The cultivated area of lettuce in China is larger than that of lettuce. Lettuce is tender, and its stems can be eaten raw, cold, fried, dried or pickled. Lettuce mainly eats leaves or bulbs. Lettuce stems and leaves contain lettuce element, which tastes bitter, hot, dry and bitter. It can enhance gastric juice, promote digestion, stimulate appetite, and has analgesic and hypnotic effects.