Cookies:
Inside your computer there are files called "Cookies". Cookies are placed into your computer when you visit websites. I own richkits.com. If you visited richkits.com on January 2nd, and then returned to richkits.com on January 23rd, I can tell that you are a returning visitor. I can tell because a cookie for my website was stored in your computer when you first visited. So when you visit richkits.com the second time, I can tell it's you again because my Cookie Program makes a record of your ip address. Most affiliate companies honor 30-day cookies. This means that if you send someone to one of your affiliate company websites, and they don't sign up or buy anything, you will still get credit if they decide to return and sign up or buy anything within 30 days. If you send someone to the affiliate company's website and they do not sign up or buy anything at first, but return to the website 35 days later, you will not get credit and will not get paid for that person. All affiliate companies are different. Some may honor 30 day cookies, some 90 day cookies, and some may not honor cookies at all. If you choose to promote an affiliate company that does not honor cookies at all, this means that you would not get credit or get paid for any referrals if the people you referred did not sign up or buy anything the first time you sent them to the affiliate website.Where to Find Affiliate Programs:
Most companies offer affiliate programs. You can check the bottom of any website's home page and look for the word "Affiliates" or "Partners" to see if that company has an affiliate program. But all the affiliates you would probably ever need can be found at CommissionJunction.com or ClickBank.com. There are many other sites like these that combine many different affiliate programs in one place, but these 2 websites are the most well known. I also check affiliate forums to see what otherpeople have said about certain affiliate programs or if they have been paid by certain companies. Below I have used Amazon.com's website as an example of where to find affiliate programs on websites. Some websites such as Amazon do not call it "Affiliates" but have their own name for it. In this example, Amazon calls their affiliate program "Associates", but it's the same thing.Thresholds
Just like any business on the internet, there are good people and bad people. It's better to choose affiliate companies that have good reputations or are well known companies. Most affiliates have a "threshold". This is a certain limit you have to reach before they pay you. For example CashCrate.com will not send you a check or pay you until you have made more than $10.00. If you made less than $10.00 than they don't have to pay you until you do. There are many companies out there who set the threshold to high amounts because they know you will never reach that amount. So if you never reach that amount, they will never have to pay you. So you will do all this work promoting their companies and they will not pay you in the end. You can usually find out what the threshold limit is for affiliate companies by checking their "Terms of Service" section or "Affiliate Conditions" section. Before you sign up for any affiliate companies, you should always check what the threshold limit is if you have never heard of the company before.