Do you mean CD or DVD players, CD-RW or DVD-RW rewriters?
If you mean rewriters, then you should also acquire a DVD-ROM player, which will also play CDs.
Rewriters are not the most robust of computer components and should be kept for their main purpose i.e, burning.
They will come with burning software such as Nero to allow you to (illegally, as so many are keen to point out) make compilations of your favourite tracks.
However, if a music firm like Sony is happy to sell you copyrighted music and another of its divisions sells the hardware that allows you to copy it (for personal use or backup of course), then I'm equally happy to slate its hypocrisy.