The CAP Theorem is comprised of three components (hence its name) as they relate to distributed data stores:

Consistency. All reads receive the most recent write or an error.

Availability. All reads contain data, but it might not be the most recent.

Partition tolerance. The system continues to operate despite network failures (ie; dropped partitions, slow network connections, or unavailable network connections between nodes.)

ibm.com/topics/cap-theorem