A stroboscope also known as a strobe, is an instrument used to make a cyclically moving object appear to be slow-moving, or stationary. It consists of either a rotating disk with slots or holes or a lamp such as a flashtube which produces brief repetitive flashes of light.

A strobe light or stroboscopic lamp, commonly called a strobe, is a device used to produce regular flashes of light. It is one of a number of devices that can be used asa stroboscope. The word originated from the Greek strobos (Greek: στρόβος), meaning “act of whirling.”

A stroboscope is an instrument that emits a series of brief, intense flashing lights atspecific intervals. When the flashing light from a stroboscope is directed onto anobject rotating at high speed (e.g., a cooling fan inside a PC), the moving fan appears to stand still.