The use of social media is the largest data collection effort in human history, with great potential for psychology and public health. I will showcase recent research highlights: (1) We show that Facebook language can predict depression before its first documentation in the medical record--I will explore what that means ethically and how we should think about the power of “algorithmic insight” in medicine. (2) We can use Twitter to understand the well-being of communities, and specifically, how happiness is about things you do, and life satisfaction is about things you have. Finally, (3) I will show that Trump was elected in 2016 because of low well-being rather than a bad economy, or a specific demographic voter profile.