Have you identified the scientist in the previous photo ...

He is also inventor of "Photophone "& "Metal detector"

He also extended his works to "Aeronautics" and "Eugenics" also.

Now at least you got some idea. 

I will give very simple clue his wife name is "Hello".

Dear students is none other than 

Alexander Graham Bell ...

He is the inventor of Telephone.

He given a big gift to his wife. He first talked to his wife named Hello with the telephone he invented. 

Hence first word that talked on telephone is Hello.

HENCE IT BECOME THE FIRST WISH ON TELEPHONE FOR EVERY BODY ...

ITS THE STORY BEHIND HELLO ...

ITS THE KNOWLEDGE WHICH CAN NOT APPEAR IN TEXT BOOKS ...

HOPE YOU GOT SOME THING FROM MY SIDE ... 

Thank you ...

 Next time i will discuss with some more good and curious things by making a tribute to graham bell. 

On his name we have bell laboratories.

          Salute Sir