Sea salt has some of the chemicals floating around in the sea water that is evaporated - table salt is a more pure version of NaCl. I can't imagine any way that it could make any difference. Maybe a tiny bit of difference in taste, but I doubt even that.
You can get sea salt at most grocery stores now. The thing about it is that it's usually extra fine, so a little goes a longer way than normal table salt.
I can tell the difference if I taste one and then the other right together, by themselves, but have never been able to see a difference in cooking.
IMO, salt is salt. No so with Martha Stewart who claims there's a few dozen different salts. But then I tend to take her with a very large pinch of salt. I say, go for the table salt and don't worry yourself over it.
Same stuff. NaCl
As far as breads are concerned; if the recipe calls for sea salt, use it.
I don't know the science of it but sea salt probably reacts different with the yeast and makes a better bread. Sea salt has more minerals in it.
I love to cook, however I'm not much of a baker but I do know that when baking you have to follow the recipes to exact measurement and ingredient for best results.
You can definitely use sea salt in your everyday cooking--I do. I need less of it than nasty table salt and it tastes better.
Kosher Salt would be the next closest thing. Sea salt is not as concentrated as regular iodized salt, so if you use it, you might want to use a little less.
I'm a serious baker and I say your bread will be fine with regular salt. However, for the future, get yourself some of this: http://www.realsalt.com/
You'll never go back to that yucky table salt again. Do you know they put chemicals in it to make it pour?
What time is dinner?
As others have said on this thread, sea salt is similar to kosher salt. I only use sea salt; I get the large crystals and have them in a salt grinder, and grind salt into a dish just the way I do pepper.
Table salt is fine. You'll never tell the difference. Whoever wrote the recipe just wanted to sound sophisticated. They probably drink bottled water, too.