Waterproofing is the technique that makes a fabric water and wind resistant. These properties can be achieved by treating with water-repelling substances or through the use of a mechanically-activated hydrophic/microporous membrane. Waterproofing is expressed in millimeters, which represent the water column height the fabric can withstand before liquid penetrates.
By windproof we mean that the fabric cannot be penetrated by strong winds. The windproof feature helps to maintain body heat, prevent sudden changes in temperature and increase comfort.