DVD ranges in capacity from 4.7 Gigabytes up to 17 Gigabytes. Two sizes for the DVD media are available: 12 cm compact disc size, or 8 cm CD-single size. A DVD can be manufactured four ways: single-sided, double-sided, single-sided with dual layers, and double-sided with dual layers.

Even though most DVD discs manufactured today are DVD-5 (single-layer, single-sided discs), all DVD discs, regardless of capacity, are made up of two platters bonded back-to-back. This double-sided manufacturing technique increases the rigidity of the media and minimizes warpage.

All compact disc media exhibit some type of warpage. When the plastic used to make a CD cools, it takes on a slight curvature as one side typically cools more quickly than the other. Slight warpage does not present a problem for the laser beam being able to read the pits. However, if the warpage is extreme, the laser will not be able to read the disc at all. Due to the increased pit density of the DVD format, the discs are more sensitive to warp in the media and must therefore be as flat as possible. One easy way of solving this problem is to bond two separate discs back-to-back. This results in improved rigidity and the slight curvature induced in manufacturing is offset by the bonding.

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