Difference between Router and Switch >>>

ROUTER
A router is a device or, in some cases, software in a computer,

that determines the next network point to which a packet
should be forwarded toward its destination.
The router is connected to at least two networks and
decides which way to send each information packet based
on its current understanding of the state of the
networks it is connected to.
SWITCH
While the network switches are capable of inspecting
data packets as they are received, determining the
source and destination device of each packet,
and forwarding them appropriately.

Conclusion..

For me, router and switch is related to each other
because routers allow several switches to be
connected to them, as a means to expand
the local network to accommodate
more Ethernet devices.