The lentil or masoor (Lens culinaris) is a brushy annual plant of the legume family, grown for its lens-shaped seeds. It is about 15 inches tall and the seeds grow in pods, usually with two seeds in each.
The plant originated in the Near East, and has been part of the human diet since the aceramic Neolithic, being one of the first crops domesticated in the Near East. With 26% protein, lentil is the vegetable with the highest level of protein other than soybeans, and because of this it is a very important part of the diet in many parts of the world, and especially South Asia which has a large vegetarian population.
A variety of lentils exist with colors that range from yellow to red-orange to green, brown and black. The colors of the seeds when removed from the pods also vary, and there are large and small varieties. They are sold in many forms, with or without the pods, whole or split. The urad bean, a species of the genus Vigna, is also referred to as "black lentil". Types of Lentils
The seeds have a short cooking time (especially for small varieties with the husk removed, such as the common red lentil) and a distinctive earthy flavor. Lentils are used to prepare an inexpensive and nutritious soup all over Europe and North and South America, sometimes combined with some form of pork. They are frequently combined with rice, which has a similar cooking time. A lentil and rice dish is referred to in the Middle East as Mejadra. Lentils are used throughout the Mediterranean regions and the Middle East.
A large percentage of Indians are vegetarian and lentils have long been part of the indigenous diet as a common source of protein. Usually, lentils are boiled to a stew-like consistency with vegetables and then seasoned with a mixture of spices to make many side dishes such as sambar, rasam and dal, which are usually served over rice (and sometimes roti).
Lentils are relatively tolerant to drought and are grown throughout the world. About half of the worldwide production of lentils is from India, most of which is consumed in the domestic market. Canada is the largest export producer of lentils in the world and Saskatchewan is the most important producing region in Canada. Eastern Washington, especially the Palouse Region, is the most important producing region in the United States. The Food and Agriculture Organization (FAO) estimates that world production of lentils totalled 3.2 million metric tons (MT) in 2003. Canada produced 520,000 MT and, according to the market analysis company STAT Communications, will likely export 400,000 MT during the 2003-04 marketing year, which runs from August to July. The FAO estimates world trade in lentils totalled 1.2 million MT in 2002, with Canada exporting 382,000 MT during the calendar year.
The optical lens is so named after the lentil (Latin: lens), whose shape it resembles. The same applies also to Greek language, where the word φακός means lens and φακή means lentil. In Persian language, a lens is referred to as adasi where adas means lentil. In Hebrew, a lens is known as adasha and adashim means lentil. In Turkish, mercek means lens and mercimek means lentil. In French the word lentille is used to mean either lens or lentil. In Serbian, word sočivo and in Croatian leća, means both lentil and lens.
 Nutritional value
Apart from a high level of proteins, lentils also contain dietary fiber, vitamin B1, and minerals. Red (or pink) lentils contain a lower concentration of fiber than green lentils (11% rather than 31%). Health magazine has selected lentils as one of the five healthiest foods. Lentils are often mixed with grains, such as rice, which results in a complete protein dish.