It is possible to connect a number of computers and other electronic devices to form what is called a computer network. The computers and devices which are part of the network can "talk" to each other and exchange information. In addition to the computers and devices which are connected, other devices are often needed for the network to operate properly. Examples for such devices include hubs and switches. A network using one technology can be connected to another one using a different technology with a component which is known as router. firewalls are commonly used to protect the network. In general, networks that use cables to connect can operate at higher speeds than those using wireless technology.