An explanation of Eric Brewer's CAP theorem, which says you cannot have more than two of Consistency, Availability and Partition-tolerance in web-based distributed systems.
A. van der Linde, J. Leit\ ao, and N. Preguica. Proceedings of the 2Nd Workshop on the Principles and Practice of Consistency for Distributed Data, page 12:1--12:4. New York, NY, USA, ACM, (2016)