An image map allows you to link certain "hotspots," in a picture or graphic, to another page or file.  The only time this would be feasible is if you have more than one link to make from one image.  For an example of an image map, CLICK HERE to visit my home page.  The marqee image on my home page is an image map.  When you click on each feature, you're taken to another page in my site.  Microsoft FrontPage makes the creation of image maps a sinch.  If you don't have this program though, it's going to be a little bit more difficult.  You'll have to create it using an online image map creator such as the CIMM - Clickable Image Map Maker.