They are so strong a pairing that we even use them to describe people --think of George Clooney and his trademark salt and pepper hair.

But where did they come from, and why do they form such a ubiquitous pairing?

Salt is essential for life, and it's been used since prehistoric times, either scraped from saltwater deposits, harvested from salty lakes, or mined from underground.

It's one of the earliest food industries, and one of the most important commodities in the world.

It makes food taste better, but it's also vital for preservation - whether of meat or vegetables.

Methods for producing and controlling it were developed by all the classic civilisations, most notably the Romans, who left their mark on modern day language with their word for salt – sal.

Roman soldiers received their salary – money to buy salt – and salads were vegetables and greens seasoned with salt.

In the medieval period salt was expensive, and frequently controlled by the state.

Huge, ornate vessels for the table were made out of gold and silver, dominating dinner tables, and indicating very clearly who was of high status.

Sitting below the salt--i.e. not on the highest table--well, clearly you weren't exactly exalted.

Having salt on the table was as much for show as practicality.

For dishes were seasoned in the kitchen, but adding salt to one's meat--with the tip of the knife--was common practice, and the uncertain noble could buy written advice on exactly how salt etiquette worked along with the even thornier question of how to carve.

But how did pepper come to join it?

It was one among a wide range of spices available to the medieval cook, and it was expensive--in the 1430s one pound of peppercorns cost as much as a pig.

In the late 15th Century, the Portuguese took control of Malabar in east India, and started cultivating black pepper on a large scale.

Prices fell, in line with over supply, and pepper became more readily available.

By the 16th Century the phrase "peppercorn rent" was in use, to mean a nominal sum.

The real boost though, came with a change in culinary fashion to favour the French.

They loved black pepper, and their chefs were busy tidying and simplifying medieval cuisine, delineating more firmly sweet from savoury, and codifying which ingredients worked with which.

Salt was obviously savoury.

Pepper tended that way, and so the fashionable French-style dishes of the next century used both, together, and with fewer and fewer other spices.

By the Victorian age, salt and pepper were coming together as standard seasonings.

However, other forms of pepper vied with black, and cayenne also appeared frequently in cookery books.

Salt was still on the table, now in small salt cellars, no longer just for the privileged few.

In 1911 the Morton Salt Company of Chicago patented an easy-flow salt and salt shakers could finally take off.

During the 20th Century, pepper shakers joined them.

Then, as package holidays introduced Brits to freshly ground pepper at the table, pepper mills replaced the shakers.

Phew.

It's not a ubiquitous combination everywhere though--other cultures might still have the salt but replace the black pepper with chilli.

And let us not forget the pickles, the sambals, the vinegars, the fish sauces and the salsas.

Can I make room on my table and have them all?