Major Types of Blood

Type A: Positive(+) Negative(-)
Type B: Negative(-) Positive(+)
Type AB: Positive(+) Positive(+)
Type O: Negative(-) Negative(-)

Type Donate To Receive From
A A or AB A or O
B B or AB B or O
AB AB only Anyone
O Anyone O only

http://www.answers.com/topic/blood-type