Difference between LAN and WAN

Local Area Networks (LANs) cover small geographical areas.

Shows multiple workstations connected in a circle,  including a server.

 Wide Area Networks (WANs) cover large geographical areas, most of them made from several LANs connected together.
Routers are used to connect LANs to WANs.
The Internet is a WAN.

Shows a WAN, made from several smaller networks, which could be local area networks (LAN). Each of the smaller networks has it's own server and multiple workstations connected.

 Generally, LANs are more secure than a WAN.