This document discusses big data and how it is used in modern marketing. It defines big data as large, diverse, and unstructured data that requires new technologies and specialists to analyze. These specialists, called data scientists, use skills such as domain knowledge, problem solving, communication, curiosity, technology expertise, and analytics to understand business goals and improve processes. The document also gives examples of how big data is used in marketing, such as tracking consumer behavior across devices and channels to optimize campaigns. Real-time bidding systems that target ads are mentioned as one application.