IP Address are divided into five classes which are:-
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Netid depicts the network of a device(node) and the Hostid depicts the actual device.
which is in the form of alphabets and characters,also represents an IP Address.For example go to command prompt in windows and type 'ping google.com' and hit enter.Then the ip which you will get,write that ip in the address bar of your browser and hit enter and you will reach google.