What is polyethylene and what do we use it for?

From wiki: Polyethylene or polythene is the most common plastic in use today. It is a linear, man-made, addition, homo-polymer, primarily used for packaging. As of 2017, over 100 million tonnes of polyethylene resins are being produced annually, accounting for 34% of the total plastics market. Wikipedia
Formula: (C2H4)n
Melting point: 115-135 °C (239-275 °F; 388-408 K)
Density: 0.88-0.96 g/cm3
Magnetic susceptibility (χ): −9.67×10−6 (HDPE, SI, 22°C)
Abbreviations: PE
Log P: 1.02620
Ethylene can exist in various types based on whether side groups exist and how long they are. High-density polyethylene HDPE has no branching, linear low-density polyethylene LLDPE has small branching, and low-density polyethylene LDPE has large branching. Applications just as parts, packaging, bottles.