Until last week I always thought a 'Tweenie' was an oversized, hyperactive, brightly-coloured children's TV character.

But it is also the name given to the computerised tour guide I was handed as I arrived at Osterley House to take part in the National Trust's new tour.

'Tweenie' is actually an abbreviation of 'between stairs', and conjures up images of a time when two intertwined worlds, those of servants and masters, coexisted in grand houses up and down the country.

Being a bit of a historynovice, I opted for the children's version, which I was told would bring the past to life by leading me from room to room, pointing out important historic features, while also keeping me entertained with fun interactive games.

My first stop was the Tapestry Room, where I was invited to play the animal anagram game, where I worked out the names of creatures which could be found printed on the decadent tapestries hanging around the room.

In the Morning Room I played my first ever harpsichord, albeit on the three inch screen hanging from my neck.

Volunteer Stuart Morgan said: "They have been a real success, although some people haven't been too keen to try them, most really enjoy it.

"Children are so good with technology these days that they tend to work out how to use it very quickly and off they go."

Wandering around in our head phones, guests young and old seemed immersed in their own worlds as they concentrated on the audio commentary and images.

Dotted around the house were also 'real life' National Trust guides who lingered in the background ready to step in when someone had a question their interactive guide could not answer.

You are still free to take the tour without the new machines, although without one I think you would miss out on information that really brings the house and its past to life, including details about the lives of the Child and Jersey families who once lived there.

On its easy to use touch screen, you can tell the digital guides which room you are in so you can spend as long as you want in each area of the house.

Not being an expert myself, and being young at heart, I found it easy to take the tour from an impatient child's viewpoint and found the hour-long circuit of the house whizzed by.

Speaking to the visitor as though they have stepped back in time, the 'Tweenie' shows servants and staff moving about the rooms you are standing in, carrying out duties like putting a warming pan in the bed in the master bedroom and polishing shoes in the hall.

Even if you have toured the house before, I think these new guides offer a chance to see it in a completely new light.

Osterley Park and House is open from March 4 to November 1, Wednesdays to Sundays and Bank Holidays. The house is open from 1pm-4.30pm and the Garden 11am-5pm. The park is open all year round. For more information call 020 8232 5050 or visit www.nationaltrust.org.uk and follow the links.