Who is considered as Manglik?
A person born under the influence of Mars (Mangala) as per Hindu astrology is said to have mangala dosha (mars defect); such a person is called a Mangalik (or Manglik). According to the superstition, the marriage between a Manglik and a non-Manglik is disastrous.
What happens if a person is Manglik?
The person born with a combination mentioned above is called a Manglik person. Since Mars is considered the planet of war, Mangal dosh creates highly unfavorable circumstances for marriage. In the married life of such persons, tensions, discomfort, unhappiness and separations are very much expected.