In general, a Hub is a central node in a network. The term comes from the analogy to a wheel's hub, the center.

A hub is a computer networking device that connects multiple Ethernet segments together making them act as a single segment. When using a hub only one computer connected to the hub is able to transmit at a time.

With a hub every attached device shares the same broadcast domain and the same collision domain.

Depending on the network topology, the hub provides a basic level 1 OSI model connection among the network objects (workstations, servers, etc). It provides bandwidth which is shared among all the objects, compared to switches, which provide a dedicated connection between individual nodes.

A hub connects computers and other devices on a local area client/server network. A cable connects the network cards on each device to one of the ports on the hub. Ethernet is the most common local area networking system (cables, network cards, and data transfer software that all work together).

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