Network

Hi
Routers are hardware devices that use software to perform routing of packets in an internetwork. Routing is the term used to define the process of taking a packet of data from a device on one network and sending it through the router to another device on a different network.

Switches are hardware devices which perform routing/passing of packets in the same network.

Hope this help you.

A router is used to route traffic between 2 or more networks.
A switch is used to connect client computers within a network.

Router
-operates at the network layer of the OSI model
-works with logical addressing, i.e., IP addresses (unlike nic cards or switches)
-used to connect two differnet network topologies (ethernet to token ring, ethernet to frame relay)
-used toconnect two different subnets using the same topology (LAN with IP network address 207.1.175.0 and LAN with IP network address 154.14.211.0)

Switch
-also known as an intelligent hub
-works at the datalink layer of the OSI model
-uses hardware addresses to transfer data (MAC addresses)
-works on a particular LAN subnet, i.e., 207.4.175.1-254 (unless you are using a VLAN switch, but that is getting a little ahead)
-switches have the ability to create routing tables. Each port on a switch "memorizes" the MAC address of all nodes that pass data through that port. For example, lets say that computer A is located on port 12, and server F is located on port 16 of the switch. When data traveling from computer A that is destined for server F reaches port 12 on the switch, the switch knows to send the data back out of port 16 to the server. This is unlike a hub, where the data would be broadcast on all the ports and only the intended recipient (server F) would actual acknowledge the broadcast.