World Blood Donor Day is celebrated every year in many countries around the world on June, 14th.  The date was selected in memory of Karl Landsteiner, the biologist who discovered the first human blood groups (ABO). This celebration first started in 2004 aiming to raise the public awareness about the need for safe blood donation (including its products) voluntarily and unpaid by the healthy person. Blood donors are the key role player at this day as they donate life-saving gifts of blood to the needed person.