Rather than answer I suggest we learn how to use search engines like duckduckgo.com, bing.com, yahoo.com and such.
On top of that, MP3 is compressed too so hours can be held in the same CD that once held 74 minutes (AudioCD.)
Bob
I have just managed to squeeze 6 hours of mp3 onto a cd and I wondered how small and how close together the pits have to be for the cd to hold this much info. I assume the pits form one long spiral, and bearing in mind how fast the disc spins, would I be right in assuming this must be many metres, kilometers long?
Many thanks
S.

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