A scintillation counter is a device used to detect and measure ionizing radiation. It works by using a scintillator material that emits flashes of light, or scintillations, when it interacts with radiation. These light flashes are then converted into electrical signals by a photomultiplier tube, allowing for the quantification of the radiation. Scintillation counters are commonly used in various fields, including nuclear medicine, radiation safety, and environmental monitoring. They are valued for their sensitivity and ability to provide real-time measurements, making them essential tools in research and safety applications involving radioactive materials.