When viewing the linking codes for programs in CJ how come there is the regular "a href" link and another "img" link? Does the "img" link serve any purpose, or could we just use the "a href" to link to the program? Does the affiliate need both links present to work properly?
You can only use the a href link. Many affiliates ignore the img link and still get all the sales. img is more for tracking purposes.
No. using just the href will get your visitor to the advertiser via cj and track ok the img usually calls for the banner or content that is displayed. if you are using ppc for example and select keyword link you will only get the basic link with no images/banners, so if you are then use this link. if you want banners/content then use the whole lot.