Polyethylene is a type of plastic that is widely used in everyday products. It is made from a process called polymerization, where small molecules called ethylene are combined to form long chains. This material is lightweight, durable, and resistant to moisture, making it ideal for items like plastic bags, bottles, and containers. There are different types of polyethylene, such as low-density polyethylene (LDPE) and high-density polyethylene (HDPE), each with unique properties. LDPE is flexible and often used for packaging, while HDPE is stronger and used for items like milk jugs and pipes. Overall, polyethylene plays a crucial role in modern life.