What is the CAP theorem?

The CAP theorem: For a distributed system it is impossible to simultaneously provide more than two out of the three guarantees Consistency, Availability and Partition tolerance.

  • Consistency: It guarantees that every node in the distributed system returns the same, most successful, recent write.
  • Availability: When every request receives a response without the guarantee that it contains the most recent write.
  • Partition tolerance: When the system continues to function and upholds its guarantees in spite of network partitions.