It is a study of family history. It studies the family relationship and ancestry. It is a popular hobby in many countries. Some people keep track of their family history information or data in a genealogy data base on their computer. Some are showed their family history using a family tree. A family tree is a diagram of the members of a family. With a family tree it is observed that how people are related for example people who are married or have children. Examples of some data that are saved in the data base are places of birth, marriages & death. The other information that are saved are sources of military service census records which show where their ancestors lived, immigration data. Education qualification, occupation or designation and even some times photographs of the ancestors. The advantages or the merits of using genealogy database are that it helps to keep the track of organized records, especially when relationships change. Thus it helps to guard several types of charts & tables. Perhaps it can be concluded that people study genealogy {that is the family history } is studied for plenty reasons, among them some reasons are someone be re-united with their family after war, family disaster, foster care or adoption, finding, leaving relatives, their ancestors track their hereditary disease. It is even used to keep the track of health that has been inherited from their ancestors.