Robert Blumen talks with Eric Brewer, who discovered the CAP (consistency, availability, partition tolerance) theorem. The first part of the show focuses on Brewer's original thesis presented at the 2000 ACM Symposium on Principles of Distributed Computing (PODC): What set of problems motivated the formulation of CAP? How was it understood at the time? What are the three types of systems that can exist (or are there only two types)? Is latency the same as a partition? The second half of the show covers Brewer's more recent retrospective article on how things have changed since then: What major insights about CAP have emerged? How has CAP impacted the architecture of real applications? How can architects use the full space of the CAP theorem to arrive at the best designs? Are some types of systems more CAP-friendly? How do CAP systems recover when partitions are healed? The show wraps up with some speculation about the next 16 years.