Entrepreneurship involves creating or discovering new ideas or opportunities for the purpose of creating value, whether economic, social, or even political – and forming a new organisation to do so. An entrepreneur is a person who practises entrepreneurship.
According to this definition, the late Steve Jobs was an entrepreneur when he founded Apple, but no longer practices entrepreneurship since he launched new innovations as a corporate manager. The founders of social networking websites Twitter and Facebook are practicing entrepreneurship.
Somebody who starts up a “copycat” company may be an entrepreneur in a limited sense, by creating value for him/herself and his/her family and intensifying price competition to the benefit of consumers. But as an act of entrepreneurship, it involves little novelty and little value creation, so is less “entrepreneurial” than, say, the launch of a new biotech company which commercialises a brand new life-saving product.