Recently there's been lots of interest in genealogy and tracing family history, with the BBC's Who Do You Think You Are? series delving into the roots of celebrities like Stephen Fry and Barbara Windsor. Computerisation of birth, death and marriage records means that you doh't need to go to the General Register Office for a day anymore - the internet can give information about ancestors at the click of a mouse.

So why should you be interested in what your ancestors got up to? Firstly, it will tell you where you've come from. It's not always obvious on the surface: who would have thought that former Tory leader Ian Duncan Smith is one-eighth Japanese? Or that Jeremy Clarkson's great-great-great grandfather was a glassware tycoon? Perhaps there is a hidden history in everyone's family, and by finding it out, you can pass the knowledge on to further generations, ensuring that it's not lost.

Here are some tips to get you started on the right track.

Write down what you know

Start with yourself, and write down your parents, then your parents' parents, then their parents, and so on. Download the template from the Ancestry.co.uk website to make things easy. Even if you can't fill in all the details now, enter what you can - families are complicated so don't worry about not knowing everything!

Start filling in the gaps

If you're unsure who your great-great-great-somebody was the son or daughter of, who they married, or exactly when they died, then checking the births, marriages and deaths is vital. The site also has indexes for the rest of the United Kingdom.

Ask the family

The bare facts of your family history won't be riveting - what makes genealogy such fun is the stories behind the people; what they got up to in their lives. You should talk to members of your family, and ask them about their relatives. Use the information you've found out. For older family members, you may need to jog their memory and remind them of a distant cousin, or an estranged nephew. Record the conversations you have with family members, so you can go back to them.

Also, ask if you can look through the attic, or that drawer that hasn't been opened in years. You could find a treasure trove of old memories - photographs of ancestors, letters, mementos, journals - that will help you build a picture of what each person was like.

Expand your research

Once you have settled on the details of your immediate family, it's time to branch out on the family tree and investigate those relatives you know little about, like great-great Aunt Gertrude, or Roger Parks, second cousin thrice removed, who lives in Australia now. As well as the resources on Ancestry.co.uk, which has records from all over the world as well as the UK, you might try contacting local genealogical societies for advice, or visiting the local library and poring through their archives. There's a wealth of information on your family just waiting to be rediscovered.

Build your family tree for free at www.ancestry.co.uk.