Here you can find explanations of phrases revolving the tire.
Are 2 winter tyres enough?
Although it seems logical and economical to fit M+S tyres on the drive wheels and keep the summer tyres on the free-running wheels, this approach does involve some very real risks. When braking the weight is transferred to the front wheels. Vehicles with rear wheel drive would then be slowed down mainly via the summer tyres on the front, which provide little grip.