A network address is the address of a particular device on a network similar to the addresses of the houses

ipv4 and ipv6 are the addressing techniques on a network

ipv4
>we are nowadays using the ipv4 ,
>each address is represented in 32 bits or 4 bytes
>e.g 192.168.1.2 ( note the 4 bytes seperated by the . )
>maximum unique ip addresses that can be given are 2^32 or 4,294,967,296

ipv6
>ipv6 is proposed for the future due to the increasing population
>it is not yet in pracrice i.e is not being used now
>each address is represented by 128 bits or 16 bytes
>e.g 109. 152. 249. 235. 207. 142. 109. 235. 135. 142. 231. 235. 207. 157. 232. 214
>maximum unique ip addresses that can be given are 2^128 or 34, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000, 000
>and dont get confused with such large values just remember that can be represented by 16 bytes and 2^128 unique ip addresses



reason for introducing ipv6 as already mentioned is that the increasing population of human beings so ipv6 will provide us the chance to attach more devices to a network but obviously it will be more complex