Christopher Steiner, author of Automate This: How Algorithms Came to Rule the World, discusses his new book. Steiner originally set about studying the prevalence of algorithms in Wall Street stock trading but soon found they were everywhere. Stock traders were the first to use algorithms as a substitute for human judgment to make trades automatically, allowing for much faster trading. But now algorithms are used to diagnose illnesses, interpret legal documents, analyze foreign policy, and write newspaper articles.