Valerie - from Saginaw, MI
Royal icing is a smooth, hard-drying icing. It is great for making 3D decorations, like flowers, that will last for quite some time. You can also thin it with some liquid and use it to flood cookies.
Royal icing is also perfect to use as a “glue” to hold decorations together. It is edible, but is not recommended for icing cakes because it dries so hard. If you'd like to decorate with a softer icing, I'd recommend making buttercream icing.