The Rh blood group system is a classification of blood based on the presence or absence of the Rh factor, a specific protein found on the surface of red blood cells. Individuals who have this protein are classified as Rh positive (Rh+), while those who do not are classified as Rh negative (Rh-). This distinction is important for blood transfusions and pregnancy, as incompatible Rh types can lead to serious health issues. The Rh factor is inherited from parents, and its presence is determined by specific genes. Approximately 85% of people are Rh positive, while 15% are Rh negative. Understanding one's Rh blood group is crucial for medical procedures, as it helps prevent complications during transfusions and ensures the safety of both mother and baby during pregnancy.