Are you serious that you dont know? Ok, I guess i'll answer seriously.
A wired router has wires going from it to the devices it routes the internet to.
A wireless router, has no wires except those that plug it in and keep it running, and, of course, the internet connection itself.
Despite the problems wireless routers solve in terms of not needing wires to connect devices, it requires wireless ports on the devices it connects. While most devices easily have usb or firewire ports for the wired router, chances are good that not all devices will support a connection to a wireless router without something like a wireless internet card.
In addition, wireless routers are prone to interference. You may lose connection for no visible reason. Since you cannot see radiowaves traversing your home, you wont know why you cannot connect.
This gives wired routers the advantage. As you know, wires can be everywhere in a typical computer setup so these circumstances with wireless routers can be overcome to ease the burden of tons of wire hanging everywhere. Hope that helps.