Within online marketing or advertising, visitors or customers are brought to a website by following a referral from an affiliate website. This affiliate website is often paid on a per referral basis. Affiliate marketing is often used in conjunction with other online marketing methods such as search engine optimisation, paid search marketing, display advertising and email marketing. Affiliate Marketing also makes reference to a marketing practice wherein a business will reward its affiliates (most commonly with cash or gifts) for each visitor or customer that has resulted from an affiliate’s own marketing strategies. Affiliate marketing remains popular with affiliates because of the wide variety of choice and very reasonable payout rates.

See also:
Cost per acquisition (CPA)
Cost per click (CPC)
Reciprocal links
Ad rotation
Ad impression
Behavioural Targeting
Contextual Marketing
RSS
E-Marketing
User Session
Deep Linking