Okay, so imagine you are painting a picture and you have a brush with really soft bristles. When you paint with this brush, the edges of your brush strokes are going to be a little blurry, right? That's kind of what a Voigt profile is, but instead of paint it's light.
When we look at light that's coming from a distant object, like a star, we can see a bunch of different colors. Each color of light has its own wavelength, which is like the distance between two peaks in a wave. But sometimes, the light from a star isn't just one color - it's a mixture of a bunch of different colors, all jumbled up. When this happens, the shape of the light can look a little bit blurry.
A Voigt profile is a way to describe this blurry shape. It's like a mathematical formula that tells us how much of each color of light is in the jumbled-up mixture, and how blurry the edges of those colors are.
Scientists use Voigt profiles to study the properties of stars and other objects in space. By looking at the shape of the light from a star, they can figure out things like how fast it's moving, how hot it is, and what it's made of. It's like looking at a painting with a really soft brush - it might not be super precise, but it can give you a lot of information about the painting as a whole.