Green Board

is a type of moisture-resistant drywall with a green paper facing, used in high-humidity areas like bathrooms and kitchens to resist mold and mildew, though it's not fully waterproof and is distinct from traditional chalkboards or modern digital boards. It's a gypsum-based panel with waxy additives, making it more durable against water than standard drywall but not suitable for areas with direct water contact, like shower stalls.