Nordic
- Cross-country
Cross-country boots, like all Nordic equipment, attach to the ski usually only at the toe of the boot and are allowed to flex at the ball of the foot similarly to a normal shoe or boot. Cross-country boots generally use one of four attachment systems; NNN (New Nordic Norm), 75mm Nordic Norm ("three-pin" binding), d-ring, or SNS (Salomon Nordic System). A new Salomon Pilot binding is now widely used for racing because it uses two connection points so that the skier has more stability and control over the ski. As these boots are intended for travel over generally flat terrain, they are optimized for light weight and efficiency of motion.
- Telemark
Telemark refers to a specific technique for making downhill turns on Nordic equipment. This has resulted in highly specialized equipment designed for better performance in a downhill setting. Until 1992 Telemark boots were basically heavy leather boots with the front of the sole adapted to the 75mm Nordic Norm. The introduction of the New Telemark Norm (NTN) binding in 2007 change the technique dramatically. Since then plastic boots have become more and more common and now make up almost all Telemark boots. Plastic allows for a laterally stiffer boot while still allowing freedom of flex at the ball of the foot through the use of bellows. Boots intended for more cross country travel generally have a lower cuff, softer flex and lighter weight. Boots specialized for downhill use have higher cuffs, stiffer flex and heavier weight. Telemark boots are almost always equipped with a rubber sole.
- Alpine Touring / Randonée
Although randonée is considered an alpine sport, it basically combines the cross-country stride for uphill portions and then conventional alpine techniques on the downhill. The equipment uses most closely compares to modern telemark systems, with a stiff plastic boot offering good downhill control, and a binding system that allows it to pivot at the toe for cross-country striding. Different models trade off light weight against downhill performance. They have a rockered, rubber sole to allow for easier walking. This means that they will not fit in ordinary alpine bindings. Instead, the interface between Alpine Touring boots and bindings is defined by ISO 9523. Other attachment methods exist and prominent amongst these are the Tech bindings and fittings that were first commercialized by Dynafit as the TLT. As yet, these are not covered by an international standard.
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