Some of the earliest evidence of salt processing dates to around 6,000 BC, when people living in the area of present-day Romania boiled spring water to extract salts; a salt-works in China dates to approximately the same period. Salt was also prized by the ancient Hebrews, Greeks, Romans, Byzantines, Hittites, Egyptians, and Indians. Salt became an important article of trade and was transported by boat across the Mediterranean Sea, along specially built salt roads, and across the Sahara on camel caravans. The scarcity and universal need for salt have led nations to go to war over it and use it to raise tax revenues. Salt is used in religious ceremonies and has other cultural and traditional significance.

Salt is processed from salt mines, and by the evaporation of seawater (sea salt) and mineral-rich spring water in shallow pools. The greatest single use for salt (sodium chloride) is as a feedstock for the production of chemicals. It is used to produce caustic soda and chlorine; it is also used in the manufacturing processes of polyvinyl chloride, plastics, paper pulp and many other products. Of the annual global production of around three hundred million tonnes of salt, only a small percentage is used for human consumption. Other uses include water conditioning processes, de-icing highways, and agricultural use. Edible salt is sold in forms such as sea salt and table salt which usually contains an anti-caking agent and may be iodised to prevent iodine deficiency. As well as its use in cooking and at the table, salt is present in many processed foods.

All through history, the availability of salt has been pivotal to civilization. What is now thought to have been the first city in Europe is Solnitsata, in Bulgaria, which was a salt mine, providing the area now known as the Balkans with salt since 5400 BC. Even the name Solnitsata means "salt works".

While people have used canning and artificial refrigeration to preserve food for the last hundred years or so, salt has been the best-known food preservative, especially for meat, for many thousands of years.

 A very ancient salt-works operation has been discovered at the Poiana Slatinei archaeological site next to a salt spring in Lunca, Neamț County, Romania. Evidence indicates that Neolithic people of the Precucuteni Culture were boiling the salt-laden spring water through the process of briquetage to extract the salt as far back as 6050 BC. The salt extracted from this operation may have had a direct correlation to the rapid growth of this society's population soon after its initial production began. The harvest of salt from the surface of Xiechi Lake near Yuncheng in Shanxi, China, dates back to at least 6000 BC, making it one of the oldest verifiable saltworks.

But chefs use salt frequently throughout every stage of the cooking process. They use different types of salt for different purposes, and they often use it much more liberally than you probably do. The result? Food that tastes — not salty — but just more like itself.

“The amount of salt — and butter — used in the restaurant world is much higher than the average home cook is used to,” Keith Sarasin, chef and owner of The Farmers Dinner and Aatma, told HuffPost. “Salting food is part of the process, and a good chef knows how to season. It’s an art form that takes a while to master.”

“Just a dash of salt brings all the flavors to the surface and makes them shine together,” said Pati Jinich, chef, cookbook author and host of PBS’ “La Frontera.” ”Home cooks can be afraid of oversalting, but in many cases undersalting leads to food that’s bland or lacks oomph.”

Ready to get the “oomph” back in home-cooked meals? Here are some top chef tips for salting food like a pro.

The timing for when you salt can be just as important as how you salt, said these experts. With most dishes, that means you need to “season in layers,” Jinich said, alternating sprinkles and frequent tastings throughout the cooking process.

Be sure to take it slow and steady. “The most important thing to know about timing is not to add too much, too soon,” Allison Arevalo, owner of Pasta Louise in Brooklyn, said. “Add a little as you go, and keep tasting your food. And when you’re boiling water for pasta, add more salt than you think. I use two tablespoons per pound of pasta when I’m cooking at home. I have a friend who always asks her husband, ‘Did you salt the water Allison’s way, or your way?’”

“Don’t salt your proteins too early,” Herve Malivert, director of culinary affairs at the Institute of Culinary Education, advised. “If you salt too early before cooking, the protein will start to denature and cure. Thirty minutes before isn’t a big deal. If you want to marinate something, don’t salt it. You can marinate with other spices, and then season with salt right before you cook.”

“Chefs salt at every stage of cooking, and then we check one last time before serving, just to be sure,” said Renee Scharoff, chef and owner of Blonde on the Run Catering. “We love salt!”

The type of salt is another factor that affects end results. Josiah Citrin, the two-star Michelin chef and owner of Mélisse, Citrin, Charcoal, Dear John’s and Openaire, said it may seem like the pros are salting up a storm, but the quality of the product makes a difference. 

“It’s fair to say that because my kitchen uses high-quality sea salt, the level of saltiness is not as intense and requires a bit more,” Citrin said. “It’s important to use high-quality salts as often as you can.”

Kosher salt was the most common “everyday” salt used by these chefs, and Diamond Crystal was the brand they mentioned the most. “The flakes are consistent and make for good measuring,” said Curtis Stone, chef and owner of Maude and Gwen Butcher Shop and Restaurant in Los Angeles.

Michelle Bernstein, co-owner of Miami’s Café La Trova, mentioned fine sea salt as her favorite for baking. And, if you live in the right place, you can even shop for salt close to home. “I love supporting smaller salt makers,” Sarasin said. “I live in the Northeast, and we have access to regional salts that are always special.”

Chef John Sugimura, of Minneapolis-based Pinku Japanese Street Food, said his loyalty remains with the familiar navy blue cylinder.

Salt was one of the most important commodities of the 18th century. We take salt for granted in our day-to-day lives but at times in history it was the difference between life and death.

Himalayan salt doesn't come from the Himalayas. It's mined deep inside the mountains of Pakistan at the Khewra Salt Mine. The pink rocks are turned into table salt, lamps, and statues, sold at a premium in Western countries. But despite pink salt's growing popularity abroad, Pakistan, historically, has seen little of the profits.

See how salt is traditionally harvested from the sea.