Modern rain jackets feature a range of technologies designed to keep you dry. The most common waterproof materials include Gore-Tex, eVent, and various proprietary fabrics that repel water while allowing moisture to escape. This breathability is crucial because it prevents you from feeling clammy and uncomfortable, a common issue with less advanced jackets. When shopping for a rain jacket, look for products that list their waterproof rating, typically measured in millimeters. A rating of 5,000 mm or above is generally suitable for light to moderate rain, while jackets over 10,000 mm can stand up to more severe conditions.