[5][6] The name is derived from the Latin word seta, meaning "bristle" or "hair", which refers to the bristly spikelets.

[7] The genus includes over 100 species distributed in many tropical and temperate regions around the world,[8] and members are commonly known as foxtail or bristle grasses.

[14] As of May 2024[update], Plants of the World Online accepted the following species:[15] Numerous species were once considered members of Setaria but have since been reassigned to the following genera: Brachiaria, Dissochondrus, Echinochloa, Holcolemma, Ixophorus, Oplismenus, Panicum, Pennisetum, Pseudoraphis, Setariopsis, and Urochloa The grains can be eaten raw, though are hard and can be bitter; boiling can reduce both of these properties.

[16] Several species are still cultivated today as food or as animal fodder, such as foxtail millet and korali (S. pumila), while others are considered invasive weeds.

[17] S. italica and S. viridis are being developed as genetic model systems for the study of monocots and bioenergy grasses.