I dont know if my research is enough or not but I could not find answers on the net.
My question is why not use bridges instead of routers. We know bridges can connect two different networks. Using bridges (or switches) we can transfer data from one network to another using the MAC address to identify the hosts.
Next, we say routers selects the best possible routes and send data to that line. It's just algorithm and so such algorithms like (Distance Vector Routing or Link State Routing) can be implemented in the bridges. Then bridges too can select best possible path and futhermore operates just using MAC addresses.
Now wouldn't this question the existence of router? And if routers don't exist then there would be no existence of IP address too.
Basically, my question is why need extra IP addressing to identify the devices. I also know people say IP is logical addressing and Bridges dont operate in Network Layer and such. So my question becomes why the exact need of Network Layer when Layer 2 can do those such things. What is the noticeable distinction between layer 2 and layer 3 such that layer 3 is essential?
I am well aware that I am missing some points. I just need to clarify my doubts with strong reasoning of need of IP addresses, Routers and Network Layer.