(HE, TEL, INT) Hardware or software that connects two or more networks. Functions as sorter and interpreter by looking at addresses and passing bits of information to proper destinations. Software routers are sometimes referred to as gateways. When multiple routers are used in a large collection of interconnected networks, the routers exchange information, so that each router can build up a reference table showing the preferred paths between any two systems on the interconnected networks. A router can have many interface connections, for different physical types of network (such as copper cables, fiber optic, or wireless transmission). It may contain firmware for different networking protocol standards. Each network interface device is specialized to convert computer signals from one protocol standard to another. Routers can be used to connect two or more logical subnets, each having a different network address. The subnets addresses in the router do not necessarily map directly to the physical interfaces of the router. The term "layer 3 switching" is often used interchangeably with the term "routing". The term switching is generally used to refer to data forwarding between two network devices with the same network address. This is also called layer 2 switching or LAN switching. Routers come in different shapes and sizes