Insular illumination

Insular illumination is when something is shining a light on a very small and specific area. Kind of like when you use a flashlight and only point it at one thing instead of lighting up a whole room. This can be really useful if you need to see something that's really small or in a hard-to-reach place. For example, a dentist might use insular illumination to help them see inside your mouth better when they're working on your teeth. It's kind of like looking through a magnifying glass or a microscope to see things better.