What are the electronics parts of a CD player
By searching the web, you'll find plenty of information.
Here's a teardown of a CD player.
http://www.youtube.com/watch?v=gpi_8Vodi5w
Here's a picture of the internals:

(source: howstuffworks.com)
Here's a basic guide to the workings http://electronics.howstuffworks.com/cd4.htm
But, the best way to find out is to take it apart.