This document summarizes key points from a special issue of the IBM Journal that focuses on applications, analytics, software, and hardware technologies for massive-scale analytics and processing big data. It begins with an introduction that defines big data and provides examples of how it is used. The remainder of the document provides summaries of 15 articles in the special issue that cover topics like governing big data, trends in massive-scale analytics stacks, designing systems for big data workloads, platforms for extreme analytics, and using big data for applications like social network analysis and underwater acoustic monitoring.