A network is a collection of devices, such as computers, smartphones, and servers, connected to share data and resources. Networks can vary in size and scope, from small home networks to vast global infrastructures like the Internet.
A LAN (Local Area Network) is a network that spans a small geographical area, such as a home, office, or school. LANs are often created by devices such as routers in your home which you may have seen as “WLAN” (Wireless LAN) if you ever looked at the router or its settings. If you’ve ever been into old-school gaming, you have likely used this kind of network to connect multiple computers to a single game of Counter-Strike, DoTA, or so many other games.
A WAN (Wide Area Network) connects multiple LANs across large distances. The Internet is the most well-known example of a WAN, linking networks worldwide.
Note: Several other definitions of networks such as a Metropolitan Area Network (MAN), and Personal Area Network (PAN) also exist but are omitted because they are not very relevant when learning about WebRTC.
The key difference between LAN and WAN lies in their scale: while LANs are confined to a local area, WANs connect networks over large distances, often using telecommunication links. These network types are useful to understand when you are trying to connect a device in your LAN to one outside it. Several concepts that are seen later in this course such as NAT Traversal, as well as infrastructure like STUN and TURN servers are used to establish connections between devices on different types of networks.