goosebumps

Goosebumps, in humans, refer to the short-lived involuntary elevation of hair on the skin, produced when the arrector pili muscles attached to hair follicles contract. This reflex, also called piloerection, is controlled by the sympathetic nervous system. Goosebumps occur in cold temperatures as part of a thermoregulatory response and can also be triggered by strong emotions such as fear, awe, or excitement. In humans the effect is largely cosmetic, since body hair is sparse and the reflex is considered vestigial in modern humans. The name comes from the rough, goose-flesh appearance of skin when hair stands on end.

Goosebumps is also the title of a long-running series of children's horror novels by R. L. Stine, begun in 1992. The books are written for middle-grade readers and feature standalone stories that end with a twist or cliffhanger. The franchise expanded to a television series (1995–1998) and to feature films, including Goosebumps (2015) and Goosebumps 2: Haunted Halloween (2018). The books are known for accessible language and a brisk, episodic style, and for popularizing a modern, kid-friendly approach to spooky tales.