Of the many different kinds of salt, the one I recommend for everyday use is coarse kosher salt, preferably Diamond Crystal, or, if that’s not available, Morton’s, which has an anti-caking agent.
The primary reason for using a coarse salt is that salt is best measured with your fingers and eyes, not with measuring spoons. Coarse salt is easier to hold and easier to control than fine salt. Salting is an inexact skill, meaning there is no way to describe in words how much salt to use in any given dish. Instead, it is up to the cook, a matter of taste. Also, people’s salt preferences differ, given one’s experience and expectations of saltiness. So always salt to taste. When a recipe for a sauce or a stew includes a precise measure of salt, a teaspoon, say, this is only a general reference, or an order of magnitude—a teaspoon, not a tablespoon. You may need to add more. How do you know? Taste the food.