Gloves and mittens for skiing, snowboarding, park & pipe, and ice climbing will balance warmth with dexterity, protecting your hands from snow and cold. They offer both waterproof or water-resistant protection, as well as some degree of insulation (usually synthetic) for warmth in frigid temperatures and during stop-and-start activities.
For really cold conditions or chronically cold hands, mittens are the best way to go. They feel warmer than gloves because they have less surface area exposed to the cold, trapping heat more effectively. Ski and snowboard mittens will nearly always feature some insulation, and often include removable liner gloves.
Lightweight gloves offer protection against the elements during aerobic activities, when insulation is not as important. These gloves are ideal for cold-weather running, hiking, cross-country skiing, and snowshoeing. They shield your hands from wind, light precipitation, and moderate cold, and enhance your grip on tools or poles.
Liner gloves are thin and lightweight, and are often made from technical fabrics that wick moisture and dry quickly. They add an extra layer of warmth under ski gloves and mittens on really cold days, or can be used in more moderate weather for activities like running. They often they feature a touchscreen-compatible fingertip so you can stay in touch without exposing your skin.