How does a non-stick pan get its surface?
The cooking surface can behave very differently from the metal body underneath because it is a deliberately engineered coating.
What is happening?
Many familiar non-stick coatings use highly polymerised fluoropolymers. During manufacture the coating is applied and heated so that it becomes strongly bound to the cookware surface. Its surface properties make foods less likely to adhere strongly during cooking.
Look inside the object
The pan underneath still has another job: spread and hold heat. Aluminium is common because it conducts heat well and is light; other constructions use stainless steel or layered combinations. The coating is therefore only one part of the thermal design.
What this object teaches us
This is a useful distinction between an object's bulk material and its surface. A layer only fractions of a millimetre thick can determine friction, wetting, adhesion and cleaning behaviour even though most of the pan is a completely different material.