What is the role of a switch in a network ?

A switch is a device that is used to segment networks into different sub-networks, called subnets or LAN segments to prevent traffic overloading.

A switch is responsible for filtering i.e., transforming data in a specific way and for forwarding packets between LAN segments. To insulate the transmission from the other ports, the switch establishes a temporary connection between source and destination and then terminates the connection once the conversation is done.