The chapter explores the extensive role of plastics in the automotive industry, highlighting their technical properties, historical development, and applications. Plastics, defined as organic polymers with additives, are valued for their light weight, corrosion resistance, thermal insulation, and moldability. Key categories include thermoplastics, thermosets, and elastomers. The chapter reviews specific polymers—such as polypropylene, polyurethane, PVC, ABS, polyamide, and PET—used in vehicle components, including bumpers, dashboards, and seats. Additionally, it examines innovations in bio-based plastics and the rising importance of recycled plastics, driven by environmental concerns. The chapter concludes by emphasizing plastics’ irreplaceable role in modern car design, weight reduction, cost-efficiency, and sustainability, while addressing end-of-life recycling challenges and closed-loop systems.