I don't understand salt. I know sea salt tastes the best, and that the U.S. started adding iodide to salt for it's health benefits. But what's the difference in sea salt, table salt, kosher salt? What are they best used for?
Recently I bought rock salt from Vietnam, calling itsself natural salt. It's not exactly pure looking and was very inexpensive. What exactly did I buy? Any ideas? Should I use it in my salt grinder or is it better suited for use in a brine?