Excuse my dumb question, but what are "covers" and how do you "cover" music?
Glad to see you back fine sir!
I don't feel that dan's explanation is quite right - "cover" versions are not necessarily "how a piece is supposed to sound".
A cover band (to put it in context) means one that plays other peoples music rather than their own. However contemporary artists that generally perform their own works, may also "cover" a song by another artist either by reproducing the original version, or reinventing the work to make it their own - such as if I were to make a jazz version of a chopin piece for example by altering the rhythm to a swing feel and replacing the LH with a walking bass (but leaving the melody and underlying harmony as written).
Technically as classical artists we are always "covering" the great composers.
However, in the sense of what the OP is saying (without viewing his post).. What I suspect it means is "figure out the melody, and the underlying harmonic structure - arrange your own version of the piece" as applied to a great many pop songs and plastered allover youtube, probably by the OP himself, who is now sick of having people ask him to write out the scores for all his arrangements.
Topic: Step-by-step tutorial to covering music on piano