A LAN is a local area network. And although local is a relative term, this usually means devices that are in your building or a group of buildings that are nearby. Because these devices are local to you, usually we have very high bandwidths to be able to communicate to those devices. The networks providing these high bandwidths usually are ethernet networks and 802.11 wireless networks.
If you're using a slower network connection than what these two can provide, then you're probably not on a local area network. If you're communicating to a location that is in another city, another country, or somewhere else around the world, then you're communicating over a WAN or a wide area network. Because of the distances involved in getting that signal from one location to another over such a long distance, these speeds are usually slower than what you might find on a local area network. And there are many different ways to accomplish this.
This could be over a. a point-to-point serial connection. It could be through MPLS or many other types of wide area network technologies.
Sometimes these wide area networks are connected with fiber that's in the ground, or you may be communicating to another location through a non-terrestrial or satellite link. If you've ever connected your phone to a pair of wireless earbuds, then you've used a personal area network or a PAN. These PAN networks can be many different technologies.
You might be using Bluetooth, which is very common. when connecting these earpods, or you might use infrared or NFC connections. These are very common in automobiles where you're connecting your mobile phone to the audio system that's in your car or your truck, and you may be able to integrate other applications such as your map or your contact list.
Connecting your wireless headset is probably one of the most common ways to connect a personal area network, and if you're working out, you may be able to use a personal area network to communicate directly to the equipment. And it's very common to create reports based on this workout telemetry that you've been able to acquire using your personal area network. If you work for a company that has many locations within the same city or geographical area, you may be connecting those sites together using a metropolitan area network or a MAN.
The distances you would need to communicate to these sites are much longer than what you would find with a local area network, but not as far as what you would find with a wide area network. This middle range of a metropolitan area network is usually with locations that are in the same city. Although in the past, there have been a number of different topologies that would connect these sites within the same city, today we commonly see metro ethernet, where you're given an ethernet connection on both sides, and the service provider provides the link between those locations.
Metropolitan area networks tend to be very common for governments because they already have the right of way to be able to put conduit in the ground and extend fiber connections between all of their remote sites. We're very accustomed to saving, loading, and changing files that are on the local drives of our computer. But there are ways to extend those drives to a centralized form of storage called a storage area network, or a SAN. A SAN is a high speed network that allows us to communicate to a centralized storage facility, usually one with a very large capacity.
This provides block level access, which is very similar to the block level access we have on our local storage devices, which means it's very efficient to read and write to that SAN. But even with these efficiencies, you may still be sending very large files and retrieving large files from this storage area network. Because of that, there are usually very high bandwidths required to be able to communicate to these SANs, and they're often isolated on their own high speed networks.
And if you're communicating wirelessly to a network that's in your building, you're probably using an 802.11 network on a wireless local area network or WLAN. These wireless networks don't have a very large range, so you often see them used inside of a building or a localized area. If you needed to extend beyond those distances, then you would usually add additional access points to be able to extend the total size of the wireless local area network.