What two characteristics give a DVD more storage capacity than a CD?

The DVD uses a red laser with a smaller wavelength, not the long wavelength red laser that is used for CDs. The shorter wavelength allows the beam to be more accurate. This accuracy means that more data can be stored on a DVD than a CD. Data can only be written on one side of a CD, but a DVD can be written on both sides depending on the type of DVD (for example, DVD-5) you have.

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