Modern winter tires differ from summer tires in two basic ways – the composition of the tread rubber and the shape of the tread pattern:

The basic property of the tread of winter tires is to maintain a hardness at low temperatures similar to that of summer tires at positive temperatures.. This is achieved by modifying the rubber composition, e.g.. towards increasing the content of natural rubbers.
A characteristic feature of winter tires is "notching” tread blocks with lots of sipes (it's narrow, most often transverse, wavy cuts). Thanks to the use of wide circumferential grooves and V-shaped tread blocks, winter tires are more resistant to aquaplaning. The special tread pattern of winter tires also gives a self-cleaning effect. Snow and melted mud are immediately thrown out of the tread cavities at high wheel speeds. Therefore, the tread may stick to the ground. In the case of all-season tires with a different compound quality, which causes high stiffness of the tire at low temperatures, it is not possible to remove snow or ice from the tread. Thus, the all-season tire can behave on snow like a tire with practically no tread in summer on slippery surfaces.