Chang, 64, started as an insurance salesman, and sold books door-to-door in the 1980s. He started Kyowon in 1985 to provide educational content to children, and quickly diversified the business. Today, the publishing giant provides home-study programmes, books and magazines to three million customers. Its myriad of businesses include hotels, electronic and beauty products, funeral and travel services.
Net worth:US$1.2 billion