The Data Container

Pre-pressed optical compact disc

A CD and DVD ROM are compact discs that contain data.

What was/is a CD used for?

When it was first made it was only used for sound, but it was later developed to store data.

Now some CD's can/ do contain more data than a computer, these CD's are worth over £1000!!!

In 2004 about 30 BILLION discs were made!!

How much data can they hold?

A usual CD can hold about 700 megabytes or 70 minutes of Audio.

A usual DVD can hold about 4.7 --> 8.5 Gigabytes.

What are they made of?

A CD is made of polycarbonate.

A DVD is made of plastic!

What does 'R' mean and 'RW' mean?

A DVD-R is a DVD that can be written once and read over and over.

A DVD-RW is a DVD that can be re-written.

What is a dual layer DVD?

A dual layer DVD is where a DVD has two layers and can hold more data than a usual DVD!
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What is a CD you ask? - Ms Poopee Doodee Reports
Fixing Scratches in CDs and DVDs