According to Wikipedia, content marketing is any marketing that involves the creation and sharing of media and publishing content in order to acquire and retain customers. This information can be presented in a variety of formats, including news, video, white papers, e-books,infographics, case studies, how-to guides, question and answer articles, photos, etc.
For the Content Marketing Institute, content marketing is the art of communicating with your customers and prospects without selling. It is non-interruption marketing. Instead of pitching your products or services, you are delivering information that makes your buyer more intelligent. The essence of this content strategy is the belief that if we, as businesses, deliver consistent, ongoing valuable information to buyers, they ultimately reward us with their business and loyalty.