B Negative is a blood type characterized by the presence of the B antigen and the absence of the Rh factor. Blood types are classified based on the ABO and Rh systems, which determine compatibility for blood transfusions. Individuals with B Negative blood can receive blood from other B Negative donors, as well as from O Negative donors, who are considered universal donors. Approximately 2% of the global population has B Negative blood, making it one of the rarer blood types. This rarity can pose challenges in emergency situations where blood transfusions are needed, highlighting the importance of blood donation and awareness of blood type compatibility.