Baba Marta is believed to be a strange old woman with a bad mood. People wear martenitsi, these adornments made of red and white yarn, to ask from Baba Marta for mercy. If the old lady is merciful she will let winter end soon so for the spring to come faster. In Bulgarian folklore, martenitsa is only gifted from friends and family and you must wear it until you see the first signs of spring, that is to see a migrating bird getting back or a blossom tree. The same tradition appears in most Balkan countries. Specifically in Greece, young children wear a red and white bracelet made of yarn to prevent becoming sunburned from sun.
Photo taken at Sofia, Bulgaria