I'm trying to understand what exactly defines a Local Area Network as such? This is how Wikipedia defines a LAN, and that sort of how it's defined anywhere else I found:

A local area network (LAN) is a computer network that interconnects computers within a limited area such as a residence, school, laboratory, university campus or office building.[1] [...] Ethernet and Wi-Fi are the two most common technologies in use for local area networks. [...]

So I understand from this that the main thing that defines a LAN as such is the geographical area size that it spans across. But I'm wondering if there isn't a more technical characteristic of a LAN?

Tell me if this paragraph is wrong:

A LAN is defined by the fact that all the computers connected to the LAN are in the same subnet, meaning they all share the same network prefix. In case one host in the LAN wants to send a packet, it looks in its routing table to see if the destination IP address is in the same network prefix, and if it is, it will send an ARP request saying "Hey, the host that has the IP address of xxxx, please send me your MAC address so I can send you a message". Whereas, if the destiation IP is not in the same network prefix, the packet will be sent to the router.

Maybe I'm confusing LAN with Private Network?

In the second paragraph of the Wikipedia definition, it says that a common technology for LANs are Ethernet and WiFi. Those are Layer 2 devices, does this mean that a LAN is a concept belonging to the Layer 2 of the OSI model? Another way of asking it: Are a group of computers connected by only a switch are considered to be a LAN?

I'd be happy for someone to clarify this one for me. Thanks !!


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