Reducing friction between the snow and ski has been the basic principal for ski waxing from the beginning and is the most developed and common form of ski augmentation.  The glide wax is chosen mostly based on the temperature of the snow. Wax acts as a layer between the ski base and the snow and provides a smooth surface to rub against the rough snow instead of having two rough surfaces rub.  The glide wax used to make skies faster is a hydrocarbon paraffin. This wax acts as a smooth layer between the bottom of the ski and the ridged surface of the snow.

 

As seen below snow has sharp points that rub against the smooth wax.

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Temperature:

    Temperature if one of the most important factors that goes into picking the correct wax. The colder the snow is the sharper it is. Snow on a very magnified level has little points. The colder the snow, the sharper the points are. The sharper points call for a harder wax. Basically the colder and sharper the snow is the harder wax one needs to use, and the warmer the snow the less sharp and the softer wax is used.