Genealogy is not a new phenomenon; people have always been interested in researching their ancestors. Because of this interest in genealogy, it is possible that someone has already done some research about your family. In genealogy terms, this research is called "previous research." There are a number of reasons why it's worth checking for previous research about your family. First, depending on what you find, you could save quite a bit of your own research time -- time that can be spent researching other branches of the family. In addition, if you find a family history or biography about one or more of your ancestors, you will probably gain access to information that is much more interesting than just the names, dates, and other facts that you might find if you were doing your own research.
You can find previous research in books such as local histories, family histories, and biographies. Good places to locate these types of books are community and genealogy libraries in the areas where your ancestors grew up and lived, large libraries such as the Library of Congress and the Family History Library of the Church of Jesus Christ of Latter-day Saints. State and university libraries are also good places to check.
You can find another source of previous research at the Family History Library; it's called the Ancestral File. The Ancestral File is a computer database that is compiled by the staff at the Family History Library. The heart of the Ancestral File comes from contributors, just like you, who submit their family trees to the Library. The Library adds people's trees to the Ancestral File or attaches them to another tree that is already in the file. All in all, the File contains about 10 million names and 1 million families. One day, we may be able to see all of mankind linked into one great big family tree! But for now, you can just use this file to find previous research about your family.
In general, it's a good idea to verify what you find through previous research. While many sources of previous research are accurate and have been recorded with great care, other sources may not be so flawless. You don't want to be led down the wrong path (or up the wrong branch!), so take the time to check the facts.
Of course, as you find more of your ancestors, you should look for more previous research. New surnames will give you new starting places to check for previous research. For more help with finding previous research about your family, see the topic Previous research about the family in the Step-by-Step Guide.