Beginning XML (and all X...things)

[maxformed]

Primary concern at my organization is website(s). Where do I begin with XML? So many off-shoots (X...things) to get confused.

Currently have a fairly static site, but many client-sites will be DB interactive, and our site may expand. Will learning XML be beneficial? All what else should I be looking for (i.e., ASP, VBScript, X...things, etc.)?

All advice appreciated.

Thanks,
Max