There are many different types of salt out there and it may seem a bit confusing, maybe this will help. If you have any knowledge/experience on this, feel free to leave a comment.
- Kosher salt: usually doesn't have any additives, cleaner taste, coarse structure, less dense (need more volume to get same amount of salt), dissolves slower/penetrates meat slower because of large structure
- Table salt: very fine, has anti-caking additives, a bit metallic tasting
- Sea salt: has natural minerals, light flavor, more expensive (note: not all sea salts are equal, different "impurities" lend different characteristic flavors)
Side note: how could salt be kosher? Kosher salt is called that because of it's large grain structure. It takes longer to dissolve and remains on the surface of meat for a long time. Blood is pulled out of the meat which is important to the koshering process. Because it's slow to dissolve, it's not recommended for baking.
Is there any difference between fresh cracked salt (like the ones they have at costco) vs salt that is already grounded up?
As for the baking properties of sea salt, it can be substituted for standard salt, but should be held back in amount as the pH and consistency can be slightly more unpredictable. In cases where pH is not an issue (cookies, brownies, muffins, etc.) I prefer sea salt to table salt for flavour and tend to add more than standard recipies.