If you're like most people, you have eight great-grandparents, and you can't name them all.
But more and more people can, thanks to a blossoming interest in genealogy. And much of this family research is being assisted, in no small measure, by personal computers and the Internet.
The first advance came several years ago with genealogy software that allowed users to build, edit and organize their family tree. It was a major boost for the genealogy craft, which had until then relied largely on paper systems of wall charts and index cards.
But now genealogy is being revolutionized yet again, this time by a burgeoning number of Web sites that allow hobbyists to search massive databases for information on their ancestors and to communicate with others about research techniques and findings.
"It's definitely the trend, and it's definitely making life easier because somebody out there probably knows something that you want to know," said David Brown, a genealogy hobbyist from Middletown, Conn.
Cyndi Howells, a genealogy enthusiast and writer in Edgewood, Wash., has seen firsthand the increased interest in online genealogy.
Her "Cyndi's List" genealogy site (http://www.cyndislist.com) made its debut in 1996 with links to more than 1,000 sites. Today, three years later, her catalog stands at more than 56,000 sites.
"Everybody is interested in family history. Everybody would like to know where they came from," Howells said. "The Internet makes a lot of the processes easier, so it encourages more people to become involved."
To Elizabeth Powell Crowe, author of "Genealogy Online: Millennium Edition" (McGraw-Hill, $19.99), the marriage of the Internet and genealogy research is a natural.
"All of a sudden, people are realizing what they need is information. And what the Internet deals with is information," Crowe said. "The Internet was created specifically to make it easy for researchers to exchange information."
One of the leading genealogy sites is RootsWeb (http://www.rootsweb.com), which hosts many discussion lists, Web sites, how-to guides and other information on tracing one's ancestors.
RootsWeb fosters communication among genealogy researchers, saving time and enabling them to make contact with people with similar interests worldwide. "It's really fundamentally revolutionizing how this research is done," said spokesman Sean Walsh.
Founded by computer scientists who were also genealogy hobbyists, RootsWeb operates as a free cooperative resource, although it does accept contributions from users. The site draws an astounding 1.7 million unique visitors each month and displays about 60 million page views.
Earlier this year, online genealogy got a major upgrade with the arrival of FamilySearch (http://www.familysearch.org), an index to the massive records archive assembled by the Church of Jesus Christ of Latter-day Saints, also known as the Mormon Church.
The church, which expects to add to the index, operates the famed Family History Library in Salt Lake City, where records on about 2 billion deceased are stored.
The rising interest in genealogy is attracting a growing number of commercial ventures.
Earlier this month , for example, A&E Television Networks, Hearst Interactive Media, Mattel Inc. and others formed a company called Genealogy.Com (http://www.genealogy.com) and gave it $37.5 million in funding. The site is a spinoff from Mattel's Broderbund software unit, which makes the popular Family Tree Maker genealogy software.
"Genealogy is really a hobby that lends itself to having a lot done via the Internet," said spokeswoman Imelda Valenzuela. "You can have access to data in your home virtually 24 hours a day."
The site offers a lot of information for free, but a subscription is required for access to some sections and databases. The cost is $9.95 a month, or $99 a year.
Ancestry.Com ( http://www.ancestry.com), and its sister sites MyFamily.Com (http://www.myfamily.com) and FamilyHistory.Com (http://www.familyhistory.com), offer users a chance not only to research their family's past but to post that information on the Internet for others to see.
"It's a lot more fun to get involved" with genealogy online, said Ancestry.Com Vice President Loretto Szucs. "It's like detective work. . . . There's an excitement that goes along with it."
The expanded availability of such resources will only fuel more public interest in genealogy, author Crowe said. "It is the most fascinating hobby because it shows you how the entire sweep of human history led inevitably to you," she said.