MODEL RELEASED. Compact disc manufacture. Worker operates plastic moulding equipment used in the production of compact discs (CDs). The machine uses injection (extrusion) moulding, and is controlled by a computer. Extrusion moulders use an extruder to push molten plastic through a desired shape. Injection moulding uses extruders with reciprocating screws that move forwards to inject the molten plastic before withdrawing to take new material to continue the process. The blank CDs made here will have data (such as music, text or images) etched onto them as a series of fine depressions on their surface.