There are three basic types of salt:
Table salt – mined using water to create a brine.
Table salt, the one found in most salt shakers, is mined from salt deposits and has most of the minerals removed. Most salt in the United States is sold with iodine added making it iodized salt. This salt is harvested by forcing water into a mine to create brine (salt/water mix). The brine is then evaporated leaving cubes of salt. The salt is refined from there to create varieties like:
Pickling salt, Canning salt, Coarse salt, Gos sel – fine grained without iodine or anti-caking preservatives.
This is similar to table salt, but lacks the iodine and anti-caking additives that turn pickles dark and the pickling liquid cloudy. Pickles made with table salt would still be good to eat, but they wouldn't look as appetizing.
Pretzel salt – large grained, does not melt quickly.
Rock salt – large crystal salt with a gray color, due to minerals not removed from normal table salt.
Popcorn salt – very fine grained salt which is flakier version of table salt.
Iodized salt – contains a small amount of potassium iodide and dextrose as a dietary supplement to prevent thyroid disease. (see Salt Composition and Medical Uses below).
Seasoned salt – table salt with herbs added like onion, hickory smoke or garlic.
Kosher salt, Koshering salt – also made from a brine but this brine is continually raked during the evaporation process.
Kosher salt is an additive-free coarse-grained salt. This salt was developed for the preparation of kosher meats in accordance with Jewish dietary laws. The salt itself is not kosher, but this is where the name comes from. The difference between table and Kosher salt is that during the evaporation process it is raked to give it a block-like structure which allows the salt to draw the blood out of meats. The raking makes Kosher salt coarser and flakier than table salt so it disperses more easily. This makes it lighter and less dense than table salt. It is also recommended to use Kosher salt for cocktail glasses for drinks like margaritas. Since it is a lighter salt, there is less after taste with it.
Today many cooks and chefs prefer it over table salt in their cooking, as it dissolves fast and its flavor disperses quickly. Kosher salt weighs less by volume than table salt, so you must increase the amount of salt used in a recipe when substituting for table salt. This is a great all-purpose salt.
Sea Salt – made from ocean or sea water, contains trace minerals not in the mined salts.
Sea Salt is just that – salt gained from evaporating salt water collected from an ocean or sea. The process is more costly then the mining process. Sea salt is typically less refined than other salts. Depending on the seawater used, you also get a variety of minerals in the sea salt. Due to this there are numerous types of sea salts. Here are a few:
Black Salt, Kala Namak, Sanchal - Significant for its strong sulfur odor (India) this salt is a pearly pink gray. It is used in Indian cooking.
Grey salt, Celtic salt, Sel Gris – Harvested from the light film of salt which forms during the evaporation process. The gray or light purple color comes from the clay in the region of France where it is harvested. Collected using traditional Celtic hand methods.
Hawaiian sea salt – Has a distinctive pink hue from the Alaea added to it. The Alaea is volcanic red clay with a high content of iron oxide. This salt is used in many traditional Hawaiian dishes like Kahlua Pig and Hawaiian Jerky.
Coarse salt, Gos Sel, Gale Grosso – Is a larger grain salt which resists moisture and is intended to be ground. Uses include flavoring for soups and salt crusts on meats.
Flake salt – Shaped like snowflakes, the brine is made using the sun and wind for evaporation. Then the brine is slowly heated to create the flakes.
Fleur de Sel, Flower of Salt, Flor De Sal – Skimmed from the top of salt ponds early in the process of evaporation, this is considered a great condiment salt; also good on grilled meats, in salads and on vegetables. The flavor, like wines, varies depending on the region it is harvested from. Typically it is from France though some is produced in Portugal.
French Sea Salt – Processed less than American salt, retains more of the mineral content gained from the Atlantic seawater it is harvested from. This usually includes natural iodine. A coarse salt, this is good for salads, vegetables and grilled meats.
Grinder salt – Large dry salt crystal which can easily be put through a grinder. With a salt grinder you want to avoid metal as the salt will corrode the grinding mechanism.
Italian Sea Salt, Sicilian Sea Salt, Sale Marino – Harvested from the lower Mediterranean sea by hand using traditional methods of natural evaporation, this salt is high in iodine, fluorine, magnesium and potassium. A delicate salt which is good on salads and in sauces.
Smoked Sea Salt - One other derivative of sea salt is a smoked sea salt. The salt is smoked over real wood fires to add the flavor to the crystals. These can be used in soups, salads, pasta and also in grilling foods like salmon.
Organic salt has different standards than organic livestock or botanicals. Some organizations have started to set up guidelines to ensure the quality of water and production process.
Lite (light) salt and salt substitutes generally do not have a great flavor. Lite salt uses potassium chloride to reduce the sodium level in the salt. Salt substitutes have little or no sodium in them. Typically only people who have a medical reason use these because the flavor is not as good as salt.
There is a product called sour salt which is not made up of salt at all, instead it is citric acid. This is used to prevent browning when canning fruit. It can also be added to rye or sour dough bread to make it more tart.