about Norwood 2..
there's no class like Norwood 0, the "perfect" head of hair is a Norwood I.
And MOST (95%+) non-balding men over 30 or so with perfect hair are Norwood 2's. They have lost a little triangular chunk of hair at both corners of their forehead (and some, especially those with low teenage hairlines will also have receded a bit in the midline ), although the rest of their hair is OK.
So if u are in your early or mid 20's, and seem to be moving very slowly from a Norwood 1 to a Norwood 2, chances are that u may just be getting the mature hairline. But u never know whether it will stop at NW2 or move further past to NW3 and beyond. So its best not to take any chances.
Cheers,
Arjun