Can anyone fully explain the longdesc and 'd' link tags. How they work, where a long description is put, if i have to link to a separate file etc?
You may be best of doing a google search for that one.
I don't think it's very well supported by browsers and like everything they display it differently.
Here's a simple example page http://www.estek.net/estek/idocs/images/_IMG_LONGDESC.html