CD vs DVD??? Is there really a difference?

They look the same…

Most people would look at a CD or DVD and think that there is no difference. Well… THERE IS! Even though the two have the same appearance, they are not the same in terms of specifications.

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Even though the two have a similar physical appearance, they have different storage sizes and can even function differently.

For example, not all CDs are used for general purpose data. Some CDs can be burned as Audio CDs, which have a limit on audio duration rather than data size. The same concept applies to DVDs in terms of Video DVDs.

Older computers and players will not be able to recognize a DVD. This is because they were built to read only CDs. So the drive will either pop the disc out or return with an error. Always check the front of the drive tray to see what types of optical media can be read with it.

This logo is printed on drives capable of reading Compact Discs (CD)
This logo is printed on drives capable of reading Digital Versatile Discs (DVD)

CompTIA A+ Practice Tests

You can find CompTIA A+ Exam Information & Practice Tests at this website:

ExamCompass has a simple practice test interface, and breaks up tests into categories as defined in the certification objective.