Week - week number. Negative values are most recent scores carried from previous years for handicap purposes.
Hcp - New Handicap after round.
Grs - Gross score.
Net - Net score, gross minus old handicap (from start of round)
Adj - Adjusted score, high scores on holes are adjusted down depending on handicap.
Cnet - course net -difference between adjusted score and par. Best five of last 10 are used to figure handicap.

The gross score will be -1 for incomplete rounds. In this case, net will still be gross minus old handicap.
The adjusted score and course net are calculated assuming the player shoots their handicap on missed holes.

See bylaws for more explanation of how handicaps are calculated.