Two of the most popular online databases are the Ancestral File and IGI, both found at www.familysearch.org. Although both are excellent resources that can jump start your research, few users take the time to fully grasp the origins of their contents. Understanding this will help you search these databases more effectively and use the results more productively.

The Ancestral File is a computerized collection of genealogies that links families into pedigrees, showing ancestors and descendants, and contains information about millions of people from throughout the world. For deceased individuals, Ancestral File shows the names of individuals, their family relationships and pedigrees; and dates and places of birth, marriage, and death. Information on living people is more limited.

It is important to know that Ancestral File depends on information contributed by individuals and genealogical organizations, and the accuracy varies accordingly. Evidence of this is the sometimes conflicting information that will appear on a single individual. Even so, it is an invaluable resource that allows you to tap into research done by others, and in some cases, contact those contributors to exchange information and compare notes. As with any other compiled record, it is good policy to verify any data found by researching the primary source.

The International Genealogical Index (IGI) is, as the name suggests, an index or tool. Most of its contents come from one of two sources: 1) individual submitters or "patrons" and 2) extractions from original records. The latter are somewhat more reliable than the former, but again, it makes sense to verify any findings by researching the primary source.

What is the IGI? Making Optimum Use of the IGI by Helen S. Ullmann, C.G.
www.livgenmi.com/fhcigi.htm

Tips on how to search the IGI
www.familysearch.org/Search/searchigi_hints.asp