What is the main difference between router and switch?

1. Switch is a layer2 device in OSI reference model & a Router is a layer3 device.

2. Switch communicate while using layer2 MAC address & Router sends packets while using IP Address.

3. Switch makes its switching table for communication & Router makes its routing table.

router is in layer3 (network layer)  and router put to packet src ip and dest ip , make something also , connecting different networks 

switch is layer2 ( Data Link Layer) put to frame src mac and dst mac , faster than brige depending on ( ASCI ) that faster on chep and IC , make broadcast for the first data only by writting it on mac-address-table

You may already know that routers define broadcast domains while switches define collision domains. A broadcast domain is defined by a single physical interface on a router. We say that switches segment collision domains because unlike hubs, each port defines a separate communication channel. In these channels collisions do not occur and transmission is made in full duplex mode (both sending and receiving of data can be done in the same time).