There are 80 million millennials — those born between 1977 and 2000 — in the United States, accounting for 25 percent of the population. This media-integrated demographic represents a very important user group for the retail industry as this population relies heavily on social networks for making e-commerce decisions. This is a generation that's growing up in a time of significant technological advancements and societal shifts that impact their decision making. Understandably, this is a highly skeptical generation, intent on using social media to make a difference and to have their voices heard.