Ski bindings are devices that attach the boot to the ski. Bindings must always be compatible with the ski boot type. Different types include alpine, snowboard, backcountry, telemark, and Kandahar.
Kandahar ski bindings are cable bindings. They secure the foot in a forward position in the binding using a cable. Cable bindings are not interchangeable with three-pin binding systems.
The New Nordic Norm (NNN) telemark ski bindings are available in both cable and three-pin styles. Three-pin style has three pins off the base with a metal clamp to attach the boot. The pins must be firmly placed into the holes on the toe of the boot. Cable bindings can be more expensive than three-pin, but are less likely to damage ski boots than pin types.
The New Nordic Norm Backcountry (NNN-BC) ski bindings are not interchangeable with NNN bindings. NNN and NNN-BC bindings are compatible with different ski boots. Some skiers consider the NNN-BC type more comfortable than the NNN systems due to the placement of the fastening hardware under the toe area rather than in front of the toe of the ski boot.
NNN-BC ski bindings are used with some telemark boots to give a lighter weight skiing system. The material of the ski boot can make a difference to the bindings. Some skiers recommend plastic boots for controlling turns, while other skiers say some plastic ski boots are heavy and less comfortable than leather or NNN-BC boots. Telemarking on sloped terrain often requires a stiffer ski boot, while backcountry skiing may require a lighter ski boot.
Alpine touring ski bindings are designed to fit the heel in a unique way: when climbing, the heel is free. This type of binding lifts the heel to keep it free while the toe area stays level while climbing. When skiing, both the heel and the toe are clamped as in alpine downhill ski bindings. Alpine touring boots, which feature a plastic shell, rigid sole, and removable inner lining, are used only with alpine touring bindings. Most of these bindings are pressure sensitive and designed to release when the weight of a falling skier makes contact with them.
Snowboard bindings are usually available in small, medium, and large. Different types have different shaped heel holders and base plates. Most snowboarders buy the snowboard first, then find the bindings that fit.