Power over Ethernet (PoE) was originally developed to provide a way to deliver both electrical power and data over Ethernet cables simultaneously. This technology was primarily designed to address the power needs of network devices (such as IP phones, cameras, and wireless access points) in a more convenient and cost-effective manner.
PoE was developed to give networked devices:
Simplified installation
Remote device power
Cost savings and reliability
Flexibility
Essentially PoE improves the ease and speed at which Ethernet devices are deployed. Over the years PoE standards have continued to develop and evolve. Today we have a several PoE standards that are used for specific use cases.