CD vs. DVD

Optical Devices:

• CD-ROMs and DVDs
• Reflect light to read data
• Bumps (Pits) are read in as 0s
• Flat areas (Lands) are read in as 1s
• Binary code translated by the computer into information

Optical discs, such as CD-ROMs and DVDs, are inexpensive media for storing large amounts of data. Optical discs use reflected light to read data. A laser beam passes over the surface of the disc and reads the data. Bumps (called pits) are read into the computer as 0s and flat areas (called lands) are read into the computer as 1s. The computer then translates this binary code into information you can use.