This document discusses social media marketing and social commerce. It describes how social commerce is a subset of e-commerce where consumers interact with others during shopping. Ratings and reviews are important for decision making but can be influenced by biases. Social shopping applications like recommendations, referrals, and forums can enhance the shopping experience. The psychology of social shopping examines how cognitive biases and herd behavior influence purchasing. Social commerce benefits include monetizing social media, increasing sales and data about customer behavior.