The Content Marketing Institute defines the term as follows:
"Content marketing is a marketing technique of creating and distributing valuable, relevant and consistent content to attract and acquire a clearly defined audience – with the objective of driving profitable customer action. "
Forbes has a great article providing real life content marketing examples.
This article builds on content developed by the Martin Trust Center for MIT Entrepreneurship for MIT's Orbit Knowledgebase and is licensed under CC BY-NC-SA 4.0.