What is a compact disc?
digital optical disc data storage format
What is it's abbreviation?
CD
Why was it invented?
to store and play only sound recording
Any other reasons?
for storage of data
Does that disc have a different name?
Yes
What?
CD-ROM
Are there other formats?
Yes
How many?
10
Name two of these?
CD-R and CD-RW
What is VCD?
Video Compact Disc
How long have CDs been available to the public?
since October 1982.
How many sales did it reach in 2004?
about 30 billion discs
How many sold around the world by 2007?
200 billion
Are they still as popular?
No
Why?
being replaced by other forms of digital storage and distribution,
Have sales dropped?
Yes
By how much?
about 50% from their peak;
How were sales in 2014?
revenues from digital music services matched those from physical format sales for the first time.
What does CD-RW mean?
rewritable media
Name another form?
Super Video Compact Disc (SVCD)