Simplify the following text for a Grade 7 native English-speaking person.
Original: John Winston Ono Lennon , MBE ( 9 October 1940 â `` 8 December 1980 ) was an English musician and singer-songwriter who rose to worldwide fame as one of the founding members of The Beatles , one of the most commercially successful and critically acclaimed acts in the history of popular music .
Simplified: John Winston Ono Lennon ( October 9 , 1940 â `` December 8 , 1980 ) was a member of the rock band The Beatles .