What is routing?

Routing is the process in which items are forwarded from one location to another. Routing is a hop-by-hop paradigm.

A Cisco router performs routing and switching functions. Describe what each function does.

Routing is a way to learn and maintain awareness of the network topology. Each router maintains a routing table in which it looks up the destination Layer 3 address to get the packet one step closer to its destination.

The switching function is the actual movement of temporary traffic through the router, from an inbound interface to an outbound interface.

What are the three types of routes you can use in a Cisco router?
The three types of routes are static routes, dynamic routes, and default routes.
What is the difference between static and dynamic routes?
Static routes are routes that an administrator manually enters into a router. Dynamic routes are routes that a router learns automatically through a routing protocol.
What is a default route?
Also known as the gateway of last resort, a default route is a special type of static route with an all-zeros network and network mask. The default route is used to route any packets to a network that a router does not directly know about to a next-hop router. By default, if a router receives a packet to a destination network that is not in its routing table, it drops the packet. When a default route is specified, the router does not drop the packet. Instead, it forwards the packet to the IP address specified in the default route.
What is a routing protocol?
A routing protocol defines the set of rules used by a router when it communicates with neighboring routers. Routing protocols listens for packets from other participants in order to learn and maintain a routing table.