"High-flange" or "large-flange" hubs have a larger flange, usually drilled out for lightness. They transmit torsional forces with less stress to the spokes than small-flange hubs do, but this is not a problem in practice with modern equipment.
High-flange hubs can make a wheel with slightly greater lateral strength than equivalent small-flange hubs, because the spokes create a wider bracing angle to the rim and shorter spokes create greater tension.
This makes them popular with track sprinters, who create greater-than-normal side loads on their wheels.
