What were the means(medium) used by first man who invented Internet?

Basm allah alrahman alrahim

do you mean media ?

first thir are some important peoples that made a big changes to the internet but not one person made the internet refere to this link >>  read more

second internet media was made to wen the war , and it still for war but in a game way !

Leonard Kleinrock is an american engineer who invented the computer networking. As per my knowledge he played influential role in the development of ARPANET, the precursor of internet. I hope, the answer is ARPANET