Affiliate marketing is cost-effective for companies and offers marketers ways to earn additional income or transition from a traditional career. The most common forms of affiliate marketing are blogs and web pages. These may be specialty blogs with a few affiliate products or entire websites built to promote products and services. Other common forms include coupon websites, review websites, email marketing programs, social media pages and groups targeting specific interests or demographics, online quizzes that lead to an opportunity to buy, and paid advertising.