beta 2 microglobulin
It is also theorized that playing cards were brought to the West via the Silk Road, a trade route that connected Eastern and Western civilizations. As playing cards reached Western countries, they gradually evolved into the decks we use today. By the 14th century, playing cards had arrived in Europe and began to become popular. In France, the deck was improved with the four suits we know today: clubs, hearts, spades, and diamonds. These cards also came with distinctive drawings that reflected the social classes: knights, queens, and kings.
