Network Hubs and Switches are devices that allow wired network devices such as desktops, laptops and printers to connect to one another.

Hubs are devices that allow all network devices to connect to one another, with no traffic or communication distinction or direction — If there are three computers (A, B and C) on the network, and computer A wants to talk to computer B, then everything they say can also be read by Computer C. The bandwidth for the entire hub is shared between all computers, and thus with many computers or lots of information being transferred, a hub can slow the entire network. In most cases, a Hub would serve the purpose of sharing network resources, but when there are many machines, a Switch may be required.

A Switch is a more intelligent version of the Hub. A Switch sees the traffic and routes it between computers, so computer A and computer B can communicate without computer C being involved. It also does this and retains the full bandwidth, so all of the devices on the network can communicate at full speed at all times.

Switches can be more expensive than Hubs, but a Switch may be required if there are four hubs on a network in a daisy chain.  This causes the network to slow down since any information sent by a computer on the network goes to all of the other machines. Connecting all four of these Hubs to a single Switch would separate the traffic, so each Hub would only expose its traffic to all of the computers on that Hub unless it were intended for a computer on another Hub. Instead of one long chain with all of the information going to all of the links in the chain, there are four small chains attached to one controller which directs the traffic as appropriate.