If you're not a builder, designer, or home improvement enthusiast, you really don't need to know all that much about drywall beyond filling small holes in a pinch. This is where purple and green drywall come into the picture. Both green and purple drywall are better at handling moisture than other options, but purple drywall is considered more water-resistant overall. Green drywall's paper layer contains a thin coat of wax that helps to wick away water and keep it from building up in the material. Purple drywall, meanwhile, is made of a gypsum core and recycled paper coating that's been specifically treated with mold and mildew resistance in mind.