The internet opens the door to compiling your family tree, genealogist John Grenham tells Rosita Boland

In the past decade or so, Ireland has seen the creation of many innovative residencies. Writers have been given such posts in many places - theatres, schools, universities, public libraries and county council offices - reaching out to the wider community.

They're not alone. Residencies have also been established for visual artists and traditional singers. Now genealogist and writer John Grenham (51) holds the distinction of having been the State's first genealogist-in-residence. He took up the position at Dublin City Library and National Archive on Pearse Street in August of last year and recently completed his term there.

"Genealogy is a great way of snooping on people," he confesses, a little abashed, in his office off the library's main reading room, in the last week of his residency. While most people's definition of "snooping" might be along the lines of opening a handbag without permission and looking inside, or illicitly reading private letters, a genealogist has something entirely different in mind. They are looking at people from a distance of generations, and the information they come up with is often relatively simple, but revealing, such as what jobs they did and what age they were when they married. "It's about trying to put the flesh on the bones of the facts," Grenham explains.

This probably best sums up the difference between genealogy and the familiar term, "looking for your roots". Genealogy tends to be a functional business, concerning itself mainly with facts: dates of births, marriages, and deaths, which fit together neatly on a wall-chart detailing of your family tree. Trying to find your roots is both more difficult but more personal, involving elements of social history. You might not get as far in exploring the outer branches and leaves of your family tree, but for some people, this matters less than trying to find out something about even a few family members that will place them in some kind of social or physical context and make them real; something more than the bare fact of their name.

"Tracing your roots is about proving you came from somewhere. Trying to identify one spot or place, whether it's a ruined house, or a graveyard or a few fields, is hugely important to some people," Grenham says. While there has long been an interest in Ireland from North America, he credits Alex Haley's 1976 blockbuster book about his family, Roots, and the TV series that followed, as popularising the attempt to discover family roots in general. "The first ingredient of curiosity is absence of knowledge," he notes sagely.

Grenham stumbled into genealogy as a career by accident. "There was no training or courses in my day," he says. "I had studied English literature and was working on a PhD on the American poet John Ashberry in UCD, with Seamus Deane. I was funding myself by working part-time at the Genealogical Office. Genealogy was all very casual in those days."

The PhD never got finished; Grenham was offered a full-time job at the Genealogical Office. He was project manager for the job of computerising the State's parish records. By 1995, when people were becoming more and more aware of the marvels of the internet, he started talking to Ireland.com about adding a genealogy element to the website. Since 1998, when www.ireland.com/ancestor launched, there have been hundreds of thousands of hits (90 per cent of the site is free), and 40,000 paid searches. Grenham continues to maintain the site.

As the library's genealogist-in-residence, Grenham was available to the public three times a week. When not helping people research their family history, he was working on the Dublin City Voters List, from 1937-1964.

"This list is a census substitute for researchers," he explains. To encourage people to be honest while completing their census forms, there is a 100-year embargo on the examination of forms. With the loss of so many records in the 1922 Public Records Office fire, the next census figures that will be available for historians and researchers will be the 1926 census, in 2026. In the meantime, the Dublin City Voters List, which was updated every year and records the names and addresses of all those on the list, is filling some of the information gaps for genealogists. "Everyone who was over 21 was entitled to vote. Since democracy was still a relative novelty, people exercised their right to vote, so the lists are quite comprehensive."

Grenham is at the year 1944 in processing these records. The aim is to turn the information into a database, with some, if not all of it, available online. "This is a way of tracing the whereabouts of people at that time," he explains. "A lot of people start getting interested in their families in the second half of their lives. They get curious. The standard piece of advice I can offer for people doing this is: talk to your elderly relatives before they die. They will give you the individual stories that records can't give you."

While the projected appearance of the Dublin City Voters List database online will assist people further in trying to trace families, it may surprise Irish readers to realise that a substantial number of Irish-related records are held not in Ireland, but in the Mormon library at Salt Lake City, Utah.

"Mormons belong to the Church of Jesus Christ and the Latter-day Saints," Grenham explains. The Mormon philosophy is that you can invite your ancestors to join the church, even if they are dead. With polygamy long associated with the Mormon church, that can mean very large extended families.

Hence the Mormon interest in tracing family records, and their extensive library of records. "One of the duties of being a Mormon is that you must explore your family history."

You do not have to be a Mormon to access the records, and many Irish-American families have used the Salt Lake City library to trace their families. While Salt Lake City has the biggest library, most Mormon temples have a history centre attached to them.

With home-ownership of computers increasingly common, and the ever-developing sophistication of the internet, people can now do a lot of searching into their background without leaving their homes.

"At its most basic level, genealogy is information and computers juggle it wonderfully," agrees Grenham. "I used to get excited when I saw an index in a book. Now the internet can offer so much." Genealogy was one of the first areas for which computer packages were developed in the 1980s.

Genealogy, by its nature, however, since it is so personal to each family, remains quite small-scale, despite the number of people attempting to discover more about their roots. "Every family is different. There have been attempts to turn genealogy into an industry, but it's a cottage industry by its nature. Most people do it by themselves."

Grenham is careful to make the distinction between genealogy and heraldry, which concerns itself with titles and coats of arms, and which is definitely an industry; often one where considerable sums of money can change hands.

Grenham has just published the third edition of his genealogy handbook, which is now three times the size it was on the first printing in 1992. "It's only in the past 10 years genealogy has become respectable in the public eye in Ireland," he says wryly, meditating on the success of the book. "In Ireland, genealogy used to be up there with heraldic golfballs."

The increasing availability of information on the internet is responsible for many of the additional pages. But despite the extra records that are being added to the internet, once you get beyond 1900, you need a specific placename if you are trying to trace your Irish ancestry.

"Since so much was lost in 1922, everything depends on the local. If you have a placename, you can trace families through local census records, church certs etc in that area. The more common your surname, the more vital it becomes to have that piece ofinformation." So has Ireland's first genealogist-in-residence done his own family tree? "Er, no," he says. "It would be too much like a busman's holiday."

Tracing Your Irish Ancestors (third edition) is published by Gill and Macmillan, €22.99