Transcription: How can a CD-ROM disk hold so much more than a conventional disk? The CD drive reads data with a beam of light so narrow that the information can be squeezed together much tighter. You see, a laser diode creates this concentrated beam of light. The light travels through a prism. Then through a lens and magnetic coil that focus the beam even more. On the underside of the compact disk itself are millions of tiny bumps called pits. That's right, the bumps are called pits. The same surface has smooth areas called lands. These pits and lands are translated into the binary language of bits and bytes ...
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