Who is the greatest musician of all time?  

im a hardcore hip-hop fan..and if im asked that question i would quickly name 50 CENT but again there is that person who makes you special and CELIN DION is my pick..she made me learn to love and learn to cry and learn to come out strong as a mule!

i am not really inclined to music but i think its mozart or beethoven...their music is a classic! and i think it will remain even for how many generations...its just my opinion although i'm not really a fan of them...i just think this coz most of the time when it is about music their names are always there...

There will never be a definite answer for this question. It all depend on people's perception and view. Besides that, what is musician? Musician can be anyone that participate in the art of music, be it composer, instrumentalist, conductor, vocalist, pop singer, opera singer, folk song singer, song writer, choir etc. Moreover, famous doesn't mean great. In modern day, most of the time it require more than a single person to produce a great music/song but often we only focus on the singer itself and give more credit than they actually should have.

For me, I would consider someone is great if their work can withstand the challenge of time (longevity) and they are multi-talented. For example:

Baroque: J.S Bach, G.F Handel, Antonio Vivaldi
Classical: W.A Mozart, Joseph Haydn, Ludwig van Beethoven, Franz Schubert
Romantic: Frederic Chopin, Felix Mendelssohn, Johann Strauss, Robert Schumann, Richard Wagner, Johann Brahms, Franz Liszt, Tchaikovsky, N.R Korsakov
20th century: Claude Debussy, Maurice Ravel, Bela Bartok, Sergei Prokofiev, George Gershwin, Benjamin Britten, Leonard Bernstein, John T. Williams, Andrew Lloyd Webber, Frank Sinatra
Pop Music: Michael Jackson; Paul McCartney, John Lennon and The Beatles; ABBA, Elvis Presley, Elton John, Bee Gees, Cliff Richard, Celine Dion, Led Zeppelin, Queen, Mariah Carey, Madonna, Bob Dylan

And even that, there are much more great musician who has produce some fantastic music pieces. Every musician has their own strength and style, so it is almost impossible to determine who is the greatest, because not all people like all kind of music. It is like comparing apple to orange. Besides that, there are much more musician who have great contribution towards certain type of music such as Edvard Grieg (Norwegian folk music), Bob Dylan (US folk music), Alan Menken (Musical theatre composer), Tim Rice (Lyricist), Shinichi Mori (Japanese Enka) etc.

I am a Hardcore fan of the musician A.R.Rahman and i admire him a lot. He is my hero and role model. Raised from a poor family, he reached great heights with this talent and hardwork. He is well known for his perseverance and he is one of the most humble guys you could have ever seen. All his dedication and hardwork won him two oscar awards for the movie SLUMDOG MILLIONAIRE and i wish he attains great height in the future days to come. Moreover he hails from my city which makes him much more a popular personality in our area and he is a kind hearted angel i have ever seen. He is organising many charity shows and he help the poor and downtrodden people to a great extent. Infact he has adopted two villages and is serving the poor and needy people there. Long live A.R.R. May God shower his blessings on you for your noble causes.

It had to be The Beatles.
They redifined music in the sixties.

One of the most famous musicians that i could ever choose from that changed the world. Hm. Only one name comes to mind when asked a question like this. IT would have to be undoubtly Bob Marley. He has most definatly changed the world with his music and his persistence. He kept on playing even on the day he was shot he felt the need to play his concert still because if evil never taakes a day off why should he?