Thermoplastics which are softened by heat and can be moulded. (Injection moulded, blow moulded or vacuum formed). Good examples are acrylic, polypropylene, polystyrene, polythene and PVC.
Thermosets which are formed by ha heat process but are then set (like concrete) and cannot change shape by reheating. Good examples are melamine (kitchen worktops), Bakelite (black saucepan handles), polyester and epoxy resins.
Composites are made by mixing materials together to get enhanced properties. Polyester resin is mixed with glass fibre to make GRP used for boatbuilding and fishing rods. Epoxy resin plus carbon fibre is stronger than steel but lighter.