The document is a summary of a 2011 TED Talk by Kathryn Schulz titled "Don't regret regret". It discusses how regret is a universal human experience comprised of denial, bewilderment, punishment, and perseveration. Regret stems from decisions made and our ability to imagine alternatives. While regret can be awful, it is important to accept our regrets as part of life, learn from them, and use them as motivation to do better rather than dwell on past mistakes. The talk encourages people not to be too hard on themselves for having regrets.