Give us each day our daily bread...

Take two bits of bread, butter, add filling and enjoy. As recipes go, it's quick, simple, and doesn't require Delia Smith to remind us how to do the basics.

If any food deserves a celebration it's the sandwich, and British Sandwich Week kicks off today with events, including a nationwide draw and the launch of a special Sandwich 2000.

There's a lot to celebrate. Commercially the UK sandwich market alone is worth more than 3.5 billion a year - that's 2.3 billion sarnies. Continental Europe too is increasingly adopting British sarnie style, with flat-bread sandwiches sales expected to match Britain by 2006.

But Britain's commercial sandwich statistics, roughly a quarter of all sandwiches consumed, are only part of the picture, and millions of home-made sandwiches account for the lion's share of consumption. The British gift to fast food was invented by its namesake, the 4th Earl of Sandwich who ordered a one-handed meal of beef between bread during an intense card game back in 1762.

He might not have recognised the houmous and lettuce creations some of us choose for lunch today, but he would certainly recognise the convenience of being able to eat on the job.

Bravo to the man who anticipated that one day even heating soup would require two minutes more than a person could spare in a day.

"We all have a lot less time for eating now," says Jim Winship, director of the Wantage-based British Sandwich Association (BSA).

"Traditional formal lunches we might have had 100 years ago are now largely non-existent. People have a lot to cram in and they expect foods to fit in with that lifestyle. That's one of the strengths of the sandwich."

But convenience is just one slice of bread. The other is the sandwich's status as one of the healthiest "fast foods" around, unless, like Elvis, you favour deep fried peanut butter and banana concoctions. Variety is the spice of sandwiches, with the never-ending taste-bud excitement of the fillings.

"A sandwich is something you can eat five days a week and not get bored," says Mr Winship, a self-confessed avocado and bacon fan.

"There's enormous scope to chose between different breads like white or wholemeal sliced, baguettes, ciabatta and pannini, to as many fillings as you can think of."

The choice of commercial sandwich fillings has grown from a limited traditional selection to an array of inventive combinations over the past twenty years. Innovative, exotic sandwich fillings now make-up 33 per cent of the market, and some sandwiches have even created cult followings. When the revolutionary Marks and Spencer's Chicken Tikka sandwich arrived back in the late eighties people began taking early lunches just to get one before they ran out. Last year, M&S, one of the most popular sandwich retailers, celebrated its 2 billionth sarnie with a record-breaking 400kg creation.

Some sandwich ventures have been less successful though.

"Someone in London once launched an alligator sandwich, which didn't last very long," muses Mr Winship.

"They also launched an ostrich sandwich, which was a bit tough to eat."

No such worries for Sandwich 2000, a mixture of sliced turkey, mango chutney, Hellmann's mayonnaise and curry powder.

The Millennium sandwich came from a nationwide recipe competition last year, with the brief to find something to "reflect the tastes and textures of the new age." It's due to go on sale on today at nationwide sandwich retailers including Sainsbury's. Demand is expected to be high.

At this point your mouth is either watering, or you're heading for dependable cheese and pickle. Because one man's sandwich is another's soggy mess and the joy is the scope sandwiches give to express personal tastes.

Research by the BSA identified five categories of commercial sandwich eater; the traditionalist with unwavering loyalty to traditional fillings, the health conscious, favouring organic or low calorie, lifestyle foodies who choose the moment's fashionable sandwiches, gourmets who tailor sandwiches to adventurous personalities and the convenience-orientated, less interested in taste, more in how quickly they can eat and run.

But despite consumer differences, there's complete free-form sandwich making going on behind closed doors. A range of breads - white, brown or fancy, crusts on or off, triangle, square or no slicing for that "ploughman-style" mouthful and most importantly no rules about fillings. A straw poll at the Oxford Mail office yielded personal favourites ranging from quirky to downright bizarre. These included Marmite and mushroom, white bread and ketchup, fishfinger and baked bean and Vegemite and hundreds and thousands, proving that with sandwiches there's no accounting for taste. Oxford Mail Editor Pat Fleming, favoured the teeth jangling banana and golden syrup. "Delicious! Give it a go!" he urged. Beyond that, the message of British Sandwich Week is that there's no better bet for convenient, creativite and healthy fast food than a sandwich, something the inventive gambling Earl would certainly have agreed with.