Difference between data and metadata

Dear all,

I am kind of confused about the definition of metadata in the context of web
services and would be very grateful for any clarification.

First question would be, if the WSDL-specification already is metadata
regarding to my web service or primary a definition of my web service (i.e.
the data which is enhanced via metadata)?  WS-Policy and WSDL-S annotations
clearly seem to be metadata, but what about a description of the
choreography with ws-cdl or a definition of security mechanism with
ws-security? data or metadata?
how would you classify standards like ws-management and
ws-reliablemessaging?

In the standard I could not find any clear specification of this term...

Thanks and kind regards,
Christian