After introducing the concept of feedback, the video focuses on characteristics of effective feedback, which is then followed by a quick mentioning of various types of feedback. The main resources for the contents of the video are quotes from articles written by Grant Wiggins, the book "How Learning Works: 7 Research-Based Principles for Smart Teaching" by Ambrose et al., Susan Brookhart's book "How to Give Effective Feedback to Your Students" and several other resources listed in references.Link to Video