It connect networks and pass data between them. It does this by using routing.
Router
It is a dedicated networking device responsible for providing a means of connecting to multiple devices. Switches can facilitate many devices (from 3 to 63) using Ethernet cables.
Switch
It allows specific devices within a network to be virtually split up. This split means they can all benefit from things such as an Internet connection but are treated separately. This network separation provides security because it means that rules in place determine how specific devices communicate with each other.
VLAN (Virtual Local Area Network)
What is the verb for the action that a router does?
Routing
What are the two different layers of switches? Separate these by a comma I.e.: Layer X,Layer Y
Layer 2,Layer 3