Foxtail millet or oodalu belongs to the Family Poaceae, Subfamily Panicoideae, Genus Echinochloa and Species Echinochloa frumentacea Link. Two barnyard millet species namely Echinochloa frumentacea and E. esculenta are under cultivation in the different parts of world. Echinochloa frumentacea (Indian barnyard millet, sawa millet, or billion dollar grass) is a species of Echinochloa. Both Echinochloa frumentacea and E. esculenta are called Japanese millet. This millet is widely grown as a cereal in India, Pakistan, and Nepal. Its wild ancestor is the tropical grass Echinochloa colona, but the exact date or region of domestication is uncertain. Echinochloa frumentacea is generally known by a few names like sanwa and jhangora (Hindi), shyama (Sanskrit), oodalu (Kannada), kuthiravaali (Tamil), kavadapullu (Malayalam), udalu and kodisama (Telugu), shamul (Marathi), sama (Gujarati), shamula (Bengali), kira (Oriya), bhagar or varai (Marathi & Chhattisgarh) and swank (Punjabi). Indian barnyard millet most probably originated from India where it has been domesticated from the wild E. colona. Wild E. colona originated from the tropics and subtropics of the Old World but can now be found in the tropics and subtropics all over the world and is very common in South-East Asia. Indian barnyard millet is known from ancient Egypt and East Africa but is at present widely grown as a cereal only in India, Kashmir and Sikkim. It has been introduced into the United States, Canada and Australia, especially as a forage. In continental South-East Asia, Indian barnyard millet is quite commonly cultivated but in Peninsular Malaysia it only occurs as a rare weed in cultivated fields. Japanese barnyard millet most probably originated from Japan where it was domesticated from the wild E. crus-galli some 4000 years ago, and was later introduced into Korea, China and adjacent Russia as a cultivated cereal. Wild E. crus-galli is native to temperate Europe and Asia but has spread to temperate and tropical areas all over the world; it is also very common in South-East Asia. Japanese barnyard millet is only extensively cultivated in Japan, Korea and northern China. Barnyard millet is an ancient millet crop grown in warm and temperate regions of the world and widely cultivated in Asia, particularly India, China, Japan, and Korea. Madhya Pradesh, Uttar Pradesh, Tamil Nadu, Andhra Pradesh, Karnataka, Maharashtra, and Bihar are among the Indian states where it is cultivated. Barnyard millet has a sweet, nutty flavour, and is easy to cook with different spices. Apart from being delicious, Barnyard millet benefits heart and kidney health. The presence of a high amount of fibre, iron, and phosphorus in Barnyard millet is helpful in controlling blood sugar, blood pressure, and cholesterol levels. It has gained more popularity in the Sattvic movement to embrace native gains that are good for both humans and the environment. It is the fourth most produced minor millet, providing food security to many poor people across the world. Globally, India is the biggest producer of barnyard millet, both in terms of area (0.146 m ha-1) and production (0.147 mt) with average productivity of 1034 kg/ha during the last 3 years. Yields of Indian barnyard millet amount to 700-800 kg/ha of grain and 1000-1500 kg/ha of straw. It is believed that it can reach a grain yield of more than 2 t/ha. As a forage crop in the United States it can produce as many as eight crops per year. Average yield of Japanese barnyard millet is 1.65 t/ha. The milling process of Foxtail millet may include husking, debranning and grinding. The husked grains are polished. Polished grain may be ground to flour. The grain can also be cooked like rice or processed for flaking. In this review article on Origin, Domestication, Taxonomy, Botanical Description, Genetics and Cytogenetics, Genetic Diversity, Breeding, Uses, Nutritional Value and Health Benefits of Barnyard Millet are discussed.