Yeast 101: Active Dry Yeast, Instant Yeast, Baking Soda, Baking Powder. Differences and Info I'm a little confused as to what are the difference between them, when should I use which?

Also, how long is the lifespan and proper care after opening of these products? If I don't bake that often can I just keep a small can in the pantry for a long while? Can they be substituted for each other?

Thanks!
Note:  I am only putting this as an answer because it is too much for a comment and because the titles show.

Many of these topics are already covered:

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Why are there no recipes combining both yeast and baking powder?

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How to convert a recipe calling for active dry yeast into rapid rise yeast?

Is there any difference between bakers yeast and regular yeast?

Does active dry yeast really need proofing?

Can active dry yeast be substituted for a compressed yeast cake in baking?

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Can/should I use rapid rise yeast for longer proofing?