Polystyrene is widely used in packaging due to its lightweight and protective properties. It is commonly found in food containers, disposable cups, and trays, providing insulation and maintaining temperature. In the construction industry, it is utilized as insulation material in walls, roofs, and floors, enhancing energy efficiency. Additionally, polystyrene is employed in the manufacturing of consumer goods such as toys, appliance housings, and electronics casings due to its durability and ease of molding. It also plays a role in medical applications, including Petri dishes and test tubes, owing to its sterility and transparency.