A Power Over Ethernet (POE) module for Arduino is an accessory that allows you to provide both data and power to an Arduino board using a single Ethernet cable. POE technology enables devices to receive power over the same Ethernet cable used for data communication, eliminating the need for separate power cables and outlets.

Here are the basic components and concepts involved in a POE module for Arduino:

• Ethernet Cable: The Ethernet cable carries both data and power. It typically uses the standard Ethernet connector (RJ45).
• POE Injector/Switch: A POE injector or switch is used at the source end to inject power into the Ethernet cable. It takes power from a power source (such as a power outlet) and combines it with the data signal, sending both through the Ethernet cable.
• POE Splitter: At the Arduino end, a POE splitter is used to separate the data and power signals. The splitter provides the necessary power to the Arduino while sending the data to its Ethernet port.