When it comes to wedding rings, the fourth finger on the left hand is traditionally considered the "ring finger". This is because in many cultures, it is believed that a vein in this finger, known as the "vena amoris," or "vein of love," runs directly to the heart. This is why this finger is commonly used for the exchange of wedding bands and engagement rings.
To symbolize the deep and genuine love shared between a newly married couple, it is a common tradition to place a ring on the finger believed to contain this "vein of love" as a representation of the union they have formed through their commitment to one another.