Ski wax is a material applied to the bottom of snow runners, including
skis,
snowboards, and toboggans, to improve their
coefficient of friction performance under varying snow conditions. The two main types of wax used on skis are glide waxes and grip waxes. They address
kinetic friction—to be minimized with a glide wax—and
static friction—to be achieved with a grip wax. Both types of wax are designed to be matched with the varying properties of snow, including crystal type and size, and moisture content of the snow surface, which vary with temperature and the temperature history of the snow. Glide wax is selected to minimize sliding friction for both
alpine and
cross-country skiing. Grip wax (also called "kick wax") provides on-snow traction for cross-country skiers, as they stride forward using classic technique.