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The DVD-R is manufactured from a clear layer of polycarbonate plastic which provides a stable base and gives the DVD physical strength. Above the polycarbonate base is a thin layer of laser sensitive dye (usually a dark green) and atop that, a thin reflective layer that reflects the laser beam back to the read head. Next is added a protective lacquer coating to which a hard polymer based coat is added to guard against scratches.

Writing data to the DVD is done by a red laser beam modulated by the serial data stream. When the beam turns "on" and hits the dye layer, a distortion (known as a pit) on the surface is made. Though it's often referred to as "burning", no actual burning or melting of any sort is done, though it does heat the dye with an 8 to 10 milliwatt beam. Just sounds more impressive to "burn" a DVD with a laser beam ! The color and composition of the dye layer is designed for maximum absorption of the red laser wavelength, thus allowing inexpensive and safe, low power laser devices to be used.

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