The document discusses big data and its applications in various domains including commerce, science, and healthcare. It provides examples of using big data for fraud detection in credit card transactions and customizing product shelves based on social media posts. It also discusses challenges in defining typical behaviors in large datasets and how approaches like building models from training data or using existing data directly can help detect outliers. The document emphasizes that big data is driving new approaches in integrative research like analyzing millions of nuclear features from whole slide images to classify brain tumors.