A "moon sign" refers to the zodiac sign that the moon was in at the time of a person's birth. It is believed to influence a person's emotions, instincts, and inner self, providing insight into their subconscious mind. While the sun sign represents one's outward personality, the moon sign reveals deeper feelings and reactions. To determine your moon sign, you need your birth date, time, and location. This information allows astrologers to calculate the moon's position in the zodiac at your birth. Understanding your moon sign can enhance self-awareness and improve relationships by highlighting emotional tendencies.