“Water resistant” and “waterproof” both refer to penetration of liquid water. Manufactured waterproof fabrics have been around for over a hundred years. They are either treated or are inherently resistant to water penetration and wetting. In Victorian times, Scottish inventor Charles Macintosh sandwiched rubber between cloth to make an impermeable fabric that was waterproof but not breathable. Raincoats were made from this material and became known as ‘macs’. However, the early designs smelled quite bad and melted in hot weather.