baking powder

Many recipes call for baking powder and baking soda? What do they do and what's the difference between them? Is this article correct? Baking Soda vs. Baking Powder: What’s the Difference?

I was about to make a savoury cornbread days ago, but when I’ve read “baking powder” I realised that I’ve never came across with it. At first I thought (wrongly) that it was baking soda or a sort of dried yeast, then I’ve found out it’s quite another thing. I’ve looked for it in a couple of...