This is layer 2 device (data link layer devices) mostly.

This is layer 2 device (data link layer devices) mostly. It is use for star topology; it is used to extend the network connectivity.

A network switch is used in a wired network ot connect to other device using ethernet cables. The switch allows each connected device to talk to the others. Wireless only networks do not use switch because devices such as wireless routers and adapters communicate directly with one another.

Although you can use the ports on the back of a router or modem to connect a few ethernet devices together, switch offer a number of advantages:

Switches allow you to connect dozens of devices.

Switches keep traffic between two devices from getting in the way of your other device on the same network.

Switches allow you to control who has access to various parts of the network.

Switches allow you to monitor usage.

Switches allow communication (withing your network) that’s even faster than the internet.

High end switches can be tailored to your network needs with pluggable modules.