Which Is The Common Type Of Blood Group And The Rarest Type Of Blood Group?

Blood groups are identified as A B AB and O. O is the most common and is considered the universal donor as it has antibodies of both the A and B blood groups. O also lacks the antigens in other blood groups that would cause agglutination of the blood and lead to possible death.
If you belong to the blood group A, you have A antigens on the surface of your red blood cells and B antibodies in your blood plasma.
If you being to the blood group B, you have B antigens on the surface of your red blood cells and A antibodies in your blood plasma.
If you belong to the blood group AB, you have both A and B antigens on the surface of your red blood cells and no A or B antibodies at all in your blood plasma. People with AB blood type are considered the universal recipient, and can receive blood from all blood types. AB- blood is considered the rarest type of blood
If you belong to the blood group  O you have neither A or B antigens on the surface of your red blood cells but you have both A and B antibodies in your blood plasma. O+ blood is the most common blood type.
There is also the RH factor. You will be either  RH+ or RH-. If you are RH+, you can receive blood from a donor that is RH-, however if you are RH-, you can't receive blood from an RH+ donor because your blood lacks the natural antibodies found in RH+ blood. However you CAN develop these antibodies, but they  are basically antibodies to your own blood.

Unsure exactly what you meant here but most of the population will be positive blood and few are negative that is a bit unusual ,I am negative and have had to have anti d after all my children because my children are all positive

Mati-f I have had 2 kids and I'm rh- to my 1st 1 is rh- and my second is postive so I don't know if the dads have the same. But gentics could tell you.