The term Local Area Network (LAN) is used to describe a network of devices in a small and limited area (a house, campus, home, office, building, etc). This type of network is usually capable of achieving high data transfer rate due to its proximity which in turn allows for the use of cheap equipment and cables. In a LAN, networks are closely connected and usually requirement one or a few network devices to connect the network devices together.

Similarly, furthermore a typical SOHO network (small office/home office) LAN consist of Wireless devices, PCs, printers, switches and/or routers, and physical cabling that connects all these network devices to communicate. The following figure shows a typical LAN:

or a more simply design:

In the first picture, we see a real-life scenario of modern day SOHO network. A small LAN with devices bonded by one or more network devices. Furthermore, the picture above we have 2 computers that are connected by a switch (Layer 2). The switch is then connected to a router (Layer 3) that provides the LAN with access to the Internet (WAN). Think about millions of LAN networks joined together to form the WAN or the Internet.

Most popular LAN technologies are Ethernet, Token Ring, FDDI, etc. LAN networks use the TCP/IP to communicate where at the Layer 1 physical layer, twisted-pair cabling is used in a LAN.

Ethernet is by far the most popular wired LAN technology, this defines the wiring, signaling, connectors, frame formats, protocol rules, etc. Most modern LANs also support the wireless LAN (WLAN) technology, defined by the IEEE 802.11 standards. Wireless LAN or WLANs use radio waves instead of wires or cables for links between devices.