Th Bavarian automaker has recently published a video in which it shows the differences between winter tyres and summer tyres in snowy conditions, with two exemplars BMW X3.
I am sure most of you already know the advantages of using the appropriate tyres during the cold season, but having a video that shows how snow tyres perform in comparison with summer tyres on surfaces covered by snow in situations like a hill start, when cornering or braking is definitely more suggestive.  

Video: Winter Tyres vs Summer Tyres

Source: BMW via YouTube