In the context of distributed systems, AP (Availability and Partition Tolerance) refers to a system design principle that prioritizes availability and partition tolerance over consistency, as outlined by the CAP theorem. The CAP theorem posits that a distributed system can only simultaneously provide two out of the three guarantees: Consistency, Availability, and Partition Tolerance. An AP system is designed to ensure that it remains available under all conditions, even in the presence of network partitions, which means that any request received by a non-failing part of the system will be responded to, albeit without the guarantee of returning the most recent write. AP systems are particularly suitable for applications where the ability to access data is more critical than the accuracy of that data, making them ideal for scenarios where service availability and resilience to network failures are paramount.