Pot scrubbing...
When stuff is burnt onto the bottom of a pot, first try simmple deglazing: hot pot, atdd water. Steam will blast much of it loose.
Then go the baking soda route. It works well for moderately serious burns.
Don't forget oven cleaner (lye) (EZOff or ...?) But DO NOT use it on aluminum! Do that outside and out of the reach of kids and pets.
Aluminum: Scrape of the worst with a metal spatula or knfe, avoiding scratching deeply. Then SOS pad.
Repolish steel with SOS pads and a circular motion to imitate the original polish marks. If seriously burned, the metal itself will be discolored, and there's nothng much you can do about that.
Copper bottoms respond well to SOS pads, cleanser, and/or lemon juice and salt. Real bad? EZOff.
Enamel? Cleanser or EZOff. SOS will scratch. Probably permanently discolored. (Bleach may help)
Cast iron? If you have a modern self-cleaning oven (the kind that lock when you're cleaning it and won't unlock until cool), put you cast iron in during a cleaning cycle. Works great, requiring washing and reseasoning afterward.
EZOff if not too seriously crudded up. Wash and reseason.
or, if terribly encrusted inside and out, use this last resort. Be careful: this is dangerous! Fill a PLASTC 5 gal bucket about 3//4 ful of water and SLOWLY add a can of LYE. (Best to wear rubber gloves and a face shield or at least goggles when working with lye.) Stir GENTLY until dissolved. Immerse the pot or skillet in the lye soluttion and leave it for 24 hours. RInse it thoroughly (you're doing this outdoors, so use the garden hose to rinse it on the lawn. ) Empty the bucket into the toilet - lifting it up to the kitchen sink might cause you to spill it..
Now wash and reseason that nice clean, gray cast iron skillet. Heat is good and hot on the stove, then turn off the heat and add a few tablespponfuls of vegetable oit (peanut's best). With a folded paper towel on a fork, wiipe the oil carefully over every bit of the inside of the skillet up to the rim. Let it cool completely, then wipe clean with a paper towel.
Done properly, you have a non-stick skillet. DO NOT ever wash it with soap or detergent: hot water and a sponge, followed by drying with a paper towel. (If you use soap, cleanser, or and SOS pad, you must reseason as above.