With some googling, I learnt that routers contain hardware firewall. But I saw in many pictures that firewall and router devices are apart as follows:
I know that there are a lot of firewall devices and also router devices in the markets separately. But what is the point? Can we say that in time, router included firewall device in itself and became 2 in 1 device? Or Can we say that firewall device means router and router device means firewall?
Note: My question is not about software firewall and router device. I'm asking you the difference between hardware firewall and router device.