A strobe is a light that flashes on and off very rapidly, creating a pulsing effect that can make movement look strange or frozen. You've probably seen strobe lights at a school dance or concert, where they make dancers seem to jump from position to position instead of moving smoothly.

The flashing happens so quickly that your eyes and brain can't keep up with normal motion. If you wave your hand under a strobe light, you might see several positions of your hand at once, like a series of snapshots. This effect occurs because the light only illuminates things during brief moments, leaving darkness in between.

Strobe lights have practical uses too. Mechanics use them to check spinning engines: the flashing can make a rapidly rotating part appear to stand still, helping spot problems. Aircraft have strobe lights on their wings so other pilots can see them at night.

The word can also be a verb. When a light strobes, it flashes repeatedly. Some people find strobing lights uncomfortable or even disorienting, which is why venues often warn audiences before using them.