David or anyone,

This is the first time I've heard about different types of CDs, can you tell me their differences and if I can play them on my ordinary cd player(not the dvd player)? (Gold CD, HDCD, XRCD XRCD2, DTS) I have a sony mini compo, that comes with a fiber optics out for CD player, I hooked that up to my onkyo 797 receiver, if I buy the DTS CD, will I be able to play it to that cd player and will have a DTS-ES output? The other format, will i be able to play them on this player as well and will hear the difference if any? Thanks...