The three types of blood cells are the following: red blood cells, white blood cells and thrombocytes.
The red blood cells carry the oxygen from lungs to tissues and the red pigment component, called hemoglobin, is responsible of oxygen transporting capacity of the red blood cells.
There exists 2 groups of three types of white blood cells, granulocytes and agranulocytes. The main function of white blood cells is to defend the body against pathogens and bacteria.
Trombocytes are the blood cells that help in formation of blood clots.