Hi Dodyskin

A couple of people answered your question correctly already, but I'll add to it a bit.

An Irish Fisherman's Afghan -- also called an Aran Afghan after the Aran Islands in Ireland -- is a knitted or crochetted kind of blanket, usually made of wool yarn. People bundle up in them during cool weather in the U.S.

Here are some good images:

http://www.kirtlandyarnbarn.com/images/bookcovers/knittersafghanaran.jpg
http://www.yarns-and.com/fabrics/Phentex/PHEaranafghan.jpg
http://members.aol.com/lffunt/ARANPICB.JPG

Hope that helps.

Dawn