This overall decline in optical disks distribution is the result of fast and convenient on-line distribution.

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But Kodak also plunged into the fiercely competitive digital storage game with recordable CD-ROMs (Photo CD) and optical disks.

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Data was stored on rewritable magneto-optical disks 2.5in (64mm) in diameter housed for protection in a square plastic shell.

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Another alternative is optical disks, which are made of plastic.

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Apple has put its computers into unibody cases, sealed in the batteries, removed the optical drives, dumped hard disks when possible and either shrunk or eliminated many once-standard connectors.

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