Graphics formats

Hi all,

I am trying to locate a vector graphic format that is a standard e.g. WMF, DXF. So.. there are lots of them!! The question I can’t seem to answer easily is whether you have to pay royalties to use such formats. I have found many lists of every graphic format know to mankind but non seem to mention whether they are free to use. Can anyone point me at a resource here? I couldnt even tell looking at various places in microsoft whether WMF was free.

Thanks in advance

NIck