WebPack Question

I am following a WebPack tutorial on Traversy Media.

He wrote a require statement that looks like this… which suppose to load a css file onto the project.

require("!style-loader!css-loader!./style.css");

I have never seen syntax like that with ! inside a require.
How he explained it is that webpack needs style-loader and css-loader.

Still, it doesn’t make much sense.
Can someone with experience with webpack explain this concept?