Not all salts are created equal. They are all sodium chloride but come from different origins and undergo different processes.
1) Table Salt. I thought it was any ordinary table salt but it isn’t. It is mined rock salt, heavily processed to removed impurities and added with anticaking substance to avoid clumping.
2) Sea Salt. The usual salt in our kitchen. The square salt crystals we often see and buy from public market, from salt vendor via takal basis. It is made by evaporation of sea water which is easy to do as we are surrounded with sea.
3) Iodized Salt. Iron deficiency leading to mental retardation and endemic goiter lead to the invention of iodized salt. It is a common problem of people away from sea. Lack of seafood consumption which are iodine rich. Minute amount of iodine is added to salt. It is the choice as we always use it everyday but we never consume it in excess. We need iodine but we should never take too much. It comes in powder, instead of crystals.
4) Rock salt. It comes from salt mines, not from sea side salt factory. It is the mineral form of sodium chloride called Halite. Mostly colorless white but certain impurities changes its color to gray, yellow, orange, red, pink or purple.
5) Pickling Salt. A salt intended for pickling. Contains no iodine, anticaking agent and other additives. Iodine is unwanted for pickling purposes, it makes the brine dark and cloudy. It is finely ground to speed up brine making.
6) Kosher Salt. Same as table salt, sodium cholride, but without the iodine and other additives, with some small amount of anticlumping agent in some brands. It has flat platelet shape as it is forced to it under pressure. Usually larger than table salt. I guess it is a classier salt type, “Kosher”.
Don’t be confused with the curing salt. It is a preservative and meat color enhancer. It is not used to make any food product salty. It is a mixture of table salt and sodium nitrite or sodium nitrate. The basic idea is the same with iodized salt. Prevent too much use and prevent consumption in case too much is added.
There are many other kinds of salts when it comes to technical chemistry. We will not dig out those.