In Japan, knowing the blood types of potential mates, politicians, even prospective employees can be essential. According to an April 29 BBC report, the workplace can be segregated by blood type and speed dating functions look to match couples up by blood type compatibility.

For years people have followed diets adhering to their blood type but relating the concept to personality has remained a largely Japanese concept that has gained popularity in South Asia, including Korea.

The importance of blood type knowledge can be directly linked to Takeji Furukawa, a Japanese professor believed to be the godfather of blood typecasting after publishing his unscientific paper in 1927, "The Study of Temperament Through Blood Type," which was reignited by Masahiko Nomi in the 1970s with his book Ketsueki-gata de Wakaru Aisho ( Understanding Affinity by Blood Type).

Today the trend has splintered into so many facets of daily life from video game character profiles, politicians including their blood type in online profiles to garner more votes, films centered on the topic and most recently with speed dating agencies that match by blood type.

So what does it all mean? Similar to astrological signs there are various ways of defining the traits of A, B, AB and O blood types but one thing is clear - B is not good in Korea and As are normally adored in Japan and make up 40% of the population. However, without any scientific grounding it has become an accepted form of discrimination known as "Burahara."

Apparently not knowing your blood type is strange in the east, so in case you intend to move to South Asia, make sure you know your type or check out the personality traits and pick one. Here is how the four blood type traits are defined by Korea4expats, a site devoted to Korean lifestyle information.

Blood Type A: conservative, introverted, reserved, patient, punctual and inclined to be perfectionists, obsessive, stubborn, self-conscious and uptight.

Blood Type B: animal-loving, creative, flexible, individualistic, optimistic and passionate, forgetful, irresponsible and self-centered.

Blood Type AB: cool, controlled, empathic, introverted and rational, aloof, critical, indecisive and unforgiving.

Blood Type O: ambitious, athletic, robust and self-confident, arrogant, insensitive, ruthless and vain.

Here is a quick guide to "Compatability by Blood Groups" per the ladies blog BellaOnline's Japanese culture editor:
A is most compatible with A and AB
B is most compatible with B and AB
AB is most compatible with AB, B, A and O
O is most compatible with O, and AB

For more insight, try: and