Light painting is taking a long exposure using a camera, and then using lasers, LEDs, fire, or any source of light, to 'paint' over the scene. To explain it simply, cameras capture light, and by leaving the sensor exposed with a long exposure time, one can use bursts of light to draw things!
Since the sensor is just sitting there, capturing all the light it sees, you can draw individual lines and shapes, and by doing them one after the other, they will all automatically be captured and added to the same image. It's pretty cool and relatively simple to do, given lights and a nice camera, but some people on the internet, as usual, have gone the extra mile and made light paintings that are more than your average laser pointer smiley face.
The Scary Rainbow Guy
The Blobby Roommate
Forever Alone Level: Light Friend
THE LIGHT VORTEX
How the Arrows Flew
Faster Than The Speed of Light
Swirls and a Girl
Arizona Summer Rain
What it Feels Like to be 10 out of 10 High
Curated from reddit.com/r/lightpainting