Nonstick Pans: Purpose, Cleaning and Heating Three newbie questions:


Purpose - I read somewhere (can't find the link again) that nonstick pans were purposefully designed to be used without oil.  Is this really true?  Or just that food generally won't stick?
Cleaning - I also read that one of the options for cleaning grease off is boiling a vinegar-water mixture, based on the principle that oil and vinegar don't mix. It seems the hazard is that the oil can stick to the back wall of the pan when pouring the mixture out.  Has anyone tried and/or have tips to prevent oil on the wall? I was thinking I'd get a paper towel and lay it on top to soak up the grease but not sure if it'll work. 
Heating - It seems that it is unsafe to heat up a nonstick pan without anything in it. How do I safely heat up the pan to the right temperature, without any oil in it?  If you put the ingredients you're to cook as it's heating up, doesn't that affect cooking the food?
Well nonstick pans were created so that the likelihood of food sticking to the surface of the pan is reduced and the idea that they were designed to be used without oil is not true. You certainly can use it with oil.

Secondly, cleaning oily residue from the pan can be done as mentioned here. It is suggesting to do the following:


Fill the pan with water
Pour in half cup of vinegar
Bring the mixture to a boil
Allowing the oily residue to float on top the surface.
Use a paper towel to skim off the residue
Pour out all the liquid in the pan
Finally, wash the pan with soapy water and non-abrasive nylon.


Thirdly, about heating nonstick pans, its alright as long as you don't cross the limit of 470 °F/243 °C as it will cause the Teflon surface to melt and release toxic chemicals. When heating up a nonstick pan empty start with a low temperature instead of going all high at the beginning which might pose a risk. The previous facts were taken from here.