-Wl vs -W1

[Andrew]

Hi,

I was wondering if anyone could point me to some docs explaining what -W1 
does, esp how it differs from -Wl. I've just been suprised to find an 
argument I thought should be -Wl only works when it is -W1 but I can't 
find any documentation on -W1 so I don't really know what it is doing. 
Googling turns up tutorials where -Wl is claimed to be the correct option 
but then in the exmaples they use -W1.

I'm rather confused and hoping someone could toss me a clue.

Thanks,

Andrew