Photon is a development framework for multiplayer games.
This reference documentation is for the .Net version of the Photon Loadbalancing and Chat API.
Many genres (shooters, card games, etc.) can be implemented easily and can be customized to be used basically any types of games. Also, in cooperation with the Photon Server/Cloud, games with server-side persistence can be built.
The Chat API allows room-independent communication with friends and in channels. The Chat API is separated from Loadbalancing and has a special task: It allows communication of users in any number of channels, independent from the matchmaking used for rooms.