What are lasers?

A laser is like a super-focused flashlight that can shine really far and really bright.

Imagine you have a regular flashlight, when you turn it on, light spreads out in all directions, like water spilling from a bucket. But a laser is more like a narrow stream of water coming straight out of the bucket, focused so tightly that it can light up things even far away.

Inside a laser, there's something called a material, maybe a crystal or gas, that gets excited by electricity. This makes the material send out light in a very orderly way. The light bounces back and forth between two mirrors, one of which is almost completely transparent. When the light comes out through that last mirror, it’s all lined up perfectly, like soldiers marching in step.

Because the light is so focused, lasers can do cool things, like cutting paper, making tiny holes in things, or even helping doctors see inside our bodies! It's like having a flashlight that doesn't spread out, it just goes straight and stays bright.