A caller is a person who prompts dance figures in such dances as line dance, square dance, and contra dance. The caller might be one of the participating dancers, though in modern country dance this is rare.
In round dance a person who performs this function is called a cuer. Their role is fundamentally the same as a caller, in that they tell dancers what to do in a given dance, though they differ on several smaller points. In northern New England contra dancing, the caller is also known as the prompter.
Callers and cuers serve slightly different functions in different types of dance. Improvisation in modern Western square dance calling distinguishes it from the calling in many other types of dance.
Callers in many dance types are expected to sing and to be entertaining, but round dance cuers do not sing and are expected to be as unobtrusive as possible.
Standardized dances such as round dance, modern Western square dance, and Salsa Rueda consist of a number of defined difficulty levels. Callers and cuers are responsible for knowing all of the calls or cues (respectively), also known as figures, for the defined difficulty level at which their dancers are dancing, as well as all figures belonging to lower or easier levels.
Callers for other types of dance may be required only to know the particular dance they are calling.
The role of a caller in modern Western square dance is not only to provide the dance steps which all of the dancers on the floor should be able to follow, but also to provide entertainment through a combination of factors, including programming, showmanship, singing ability, and challenging choreography.
Part of the entertainment factor can come from the caller's use of "patter" — a set of rhyming words and rhythms that complement the names of the dance steps being called. Patter can not only be entertaining because it is innovative and surprising, but it can also fill in the space between lengthy dance patterns, helping boost up the energy during potentially dull moments.