The art of giving dance instruction to the participants of a Barn Dance or Square Dance. Sometimes an integral member of the band who play music for the dance and sometimes 'freelance'. The caller will judge the dancers' ability and select dances from their repertoire to match or challenge them. The idea is for everyone to enjoy themselves.
Many dances are laid down as set sequences (possibly with local variations) - see Circassian Circle or The Lancers but sometimes, especially in Western Barn Dancing, the calling may be improvised and spontaneous.
Typically, the caller will walk the dancers through the dance once or maybe twice before the band kicks in with music. Once the dance is under way, the caller will continue with all or part of the instructions until it is clear that all sets have mastered the dance.