Laser

Lasers are like super-powered flashlights. Unlike a flashlight that produces a beam of light that spreads out as it travels away from the light, a laser produces a beam of light that is very narrow and stays focused over long distances. Laser light is special because all the light waves that make up the beam are in step with each other, meaning that they all have the same frequency, wavelength, and direction. This makes laser light very powerful, which is why we use lasers for many things, from seeing in the dark to cutting through very hard materials.