A programmable logic controller (PLC) includes a program executor that executes a control program, a value log collector that collects logs of device values stored in a memory during execution of the control program, an event log collector that collects logs of predetermined events occurring inside the PLC and including operation events on the device values, a communication log collector that collects logs of communication data transmitted or received by a communicator responsible for communication via a network, a time information acquirer that acquires time information indicating time, and a provider that provides the logs of the device values, the logs of the predetermined events, and the logs of the communication data in association with the time information indicating times of collection of the individual logs.