Have you ever heard of a "green screen"? Meteorologists across the country use this technology to help bring a picture to your TV screen at home on a daily basis – but what exactly is it?

A green screen is more commonly referred to in the TV business as a chromakey. It is a vertical wall or section that is converted green, sometimes by paint, sometimes with a sheet.

That part doesn’t matter as long as the surface is smooth! Its capabilities do so much for our industry.

Here’s how it works: The term chromakey comes from the process of isolating the color green and using computer software to make anything that is green invisible or transparent. Since anything green is now see-through, the key allows for another image to show up in those green areas. In the case of meteorologists, we choose to put weather graphics in that slot, but any image can be transposed.

Why the color green? The biggest reason is for contrast purposes. In order for chromakey technology to work, there must be a big contrast between what you want to show and the color you’re using to make it show. Bright green is not a color that is commonly worn by many on air talent (except on St. Patrick’s Day) so that is why the industry commonly chooses a green hue. Technically, any color could be used. In some TV stations around the country, a blue wall is used. That is very limiting on a wardrobe.

Whatever the color of the wall you have, you can no longer wear it! If you do, your outfit will disappear!

Here are a few examples of what that looks like: