What are Cookies?
These aren't the kind your grandma makes. Cookies in the computer world are small text files that Web sites place in your computer to help your browsers remember specific information. For example, they might store your passwords and user IDs. They are also used to store your preferences for content or personalized pages. Most shopping carts use cookies. These allow you to choose items and leave the virtual store, then return later and find that all the items are still in your shopping cart.

Cookies are also used to build a profile of which sites you visit and which banner ads you click on. Advertisers use this information to deliver targeted ads directly to your computer. Some sites save your preferences on the cookie itself. Other sites assign users ID numbers or encoded passwords and keep records of your preferences at their end. Some sites use temporary cookies (called session cookies) that are deleted when you exit your browser. Others place persistent cookies, which stay on your hard drive for long periods. These are the kind that you hope your affiliate programs are using.

Keeping Track of Cookies
The data from these cookies is collected and automatically analyzed by affiliate program software. Tracking provides the frequency control, accounting, stats data and anti-fraud components of a campaign. Actions such as clicks, leads, sales, impressions, and returned sales can be tracked with good tracking software. Merchants with private affiliate programs may not offer tracking data for their affiliates. It is up to affiliates to make sure that they choose honest merchants to work with who will credit them for all sales in a timely manner. Trusted third parties, like Commission Junction can take care of this for both parties so cookies are tracked in a professional manner and no sales or traffic goes unaccounted for.

Cookie Duration
How long affiliates receive credit for a sale after the initial click is determined by cookie duration. This means that if a visitor clicks through an affiliate link but doesn't purchase anything at the merchant site, and then comes back later you will still earn money for the sale. Obviously, the longer the cookie duration lasts the better for affiliates.

Commission Junction calls this the "Action Referral Period" and defines it as "The amount of time an advertiser allows their cookies to remain active for visitors that you refer to their site. Commission Junction is able to credit a referring publisher (you) for a configurable tracking duration period. This means that if you refer a visitor to an advertiser's site, a tracking cookie is set on that visitor's machine. Then, if that same visitor decides to buy something at the advertiser's site or fill out a lead form within the life span of the cookie, you will still get credit for the referral. The standard duration is 45 days; however, the cookie can be set from between 1 and 120 days."

Cookies all Around
To sum up, you make more money as an affiliate with longer cookie durations, and with affiliate programs that have effective tracking systems in place. Use trusted third party affiliate networks if you are concerned about payment and tracking. Make sure you know the cookie duration of the affiliate programs you sign up for to get maximum credit for your clicks. - All this talk of cookies calls for a glass of milk. Cheers!