Cookie duration is the time a link stays active after someone clicks it. If a link has a 24-hour cookie, it means you’ll only get credit if the person buys within 24 hours. But if it's 30 days, then even if they buy a few weeks later, you can still earn from it. This can really make a difference in your sales. Some people don't buy right away. They might come back later after thinking it over. So a longer cookie gives you a better chance of earning. It's something worth paying attention to when joining an affiliate program. The longer the cookie, the better your chances. Have you looked into how cookie length could affect what you promote?