Polyethylene, renamed poly(ethene), is a thermoplastic commodity heavily used in consumer products (over 60 million tons are produced worldwide every year). Its name originates from the monomer ethene, previously named ethylene, used to create the polymer.
In the polymer industry the name is sometimes shortened to PE, similar to how other polymers like polypropylene and polystyrene are shortened to PP and PS, respectively. In the United Kingdom the polymer is called polythene.

Polytetrafluoroethylene (PTFE) is a fluoropolymer discovered by Roy J. Plunkett (1910–1994) of DuPont in 1938.[1] It was introduced as a commercial product in 1946 and is generally known to the public by DuPont's brand name Teflon®.