The markka was Finland’s money before the euro, the way some countries once had their own notes and coins and later joined a shared currency. People paid in markkaa, and old prices in Finnish stories or museums are often in this unit. You will meet it in history, travel writing, and family talk about “before the euro”, not at a cash desk today. Though actually, English also has mark for other old European money, such as the German one; they are related, but the Finnish word is spelled markka, with two k’s.