If you are trying to decide between a wired or wireless home security system, it might help if you understood how a wired security camera system works. Wired security systems work by using cables for the power, for the internet connection, and for the video transmission.
A cable connects the cameras to a recorder. Then the recorder connects to your internet router. The power source needed is either a separate power cord or a PoE (power over the Ethernet) cable. A PoE-enabled system uses a single Ethernet cable to supply your camera both power and an internet connection, thus reducing the clutter of wires.