Panicum miliaceum is an annual cereal grain in the family Poaceae, commonly known as proso millet, broomcorn millet, or common millet. The genus name Panicum derives from Latin, referring to millet or panic grass, while the species epithet miliaceum comes from Latin milium, meaning “millet,” emphasizing its long-standing role as a grain crop. It is one of the oldest domesticated cereals, believed to have originated in northern China and Central Asia, where it was cultivated as early as the Neolithic period before spreading across Eurasia into Europe, the Near East, and South Asia. The common name proso millet comes from various Slavic languages, where proso (просо) translates directly to "millet".

The plant is characterized by an upright growth habit with slender stems, narrow leaves, and loose, open panicles bearing small, rounded seeds. It is highly drought-tolerant and has a short growing season, making it well adapted to arid and semi-arid environments where other cereals may fail. Historically, Panicum miliaceum played a major role in early agricultural systems in northern China and parts of Eastern Europe, and it remains an important minor cereal crop in regions with challenging climates.

As a food source, Panicum miliaceum produces small, starchy grains that can be cooked whole, ground into flour, or processed into porridges, flatbreads, and fermented foods. In East Asia, it has been used traditionally for congee-like preparations and fermented grain products, while in Eastern Europe it appears in porridges and rustic breads. The grain has a mild, slightly nutty flavor and cooks relatively quickly compared to many other cereals. It is also widely used as bird feed and livestock feed due to its nutritional profile and ease of cultivation.

Nutritionally, proso millet is a source of carbohydrates, dietary fiber, and plant-based protein, as well as micronutrients such as magnesium, phosphorus, and B vitamins. It contains bioactive compounds including phenolic acids (such as ferulic acid), flavonoids, and small amounts of tannins, which contribute antioxidant activity. Like other cereals, it contains starch as its primary energy storage compound, with varying proportions of amylose and amylopectin influencing its cooking properties.