The hub is the simplest networking device. Basically, what it does is interconnect the computers of a local area network (also called LAN – Local Area Network) using Ethernet cables (as a rule, the Ethernet standard).
When the hub receives data from a computer (i.e., a node), it simply relays the information to all other devices in the network.
At this point, no other computer can transmit data. This is only possible when the Hub has transmitted the previous data.
A hub can have several ports, i.e., entries for connecting the network cables from each computer. There are devices that carry eight, 16, 24 and 32 ports, for example. The number varies according to the model and manufacturer.
Note that if one or more nodes are disconnected for any reason (cable fault, for example), the network will continue to work, after all, it is the hub that maintains it.
It is also possible to “chain” hubs, i.e., to connect one hub to another to increase the number of nodes that make up the network.
The problem is that hubs are very limited by current standards. It is not possible to use them to connect the LAN to the Internet, for example. Therefore, they have fallen into disuse.
Only very specific applications, such as tools that analyze traffic on a local network, still find hubs useful.