MAC Address vs IP Address Purpose.

Hi fellas,

Over the years i have been in this field and i know the use of IP Address
and MAC address.

How is MAC address purpose different from IP address purpose with respect
to a WAN and a LAN ?

I know we have to map a physical Address with our logical address for
communicating to any other host.

But what does exactly the purpose of MAC add IP address ?

Can anyone be very specific with the answer?

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