What is/are your the most favourite composer s ?

In no particular order, and not complete: Bach (& sons), Vivaldi, Copeland, Stravinsky, Vaugh Williams, Ravel, Handel, Tchaikovsky, Sibelius, Gershwin, Debussy, R. Strauss...

Really, I wish I knew much more than I do about 'classical' music. I'm not as big on Mozart, Beethoven, Brahms, etc., or piano music or opera, as I am on early music and 'modern' (20th century) music, but most of what you hear is high classical and romantic period warhorses. I'm not much of a concerto guy either - I like chamber or full orchestral pieces better. I enjoy listening to Minnesota Public Radio's "Music Through the Night" on my local NPR classical station for less often heard fare.

Swklein, thank you for pointing out that the question did not stipulate "classical" - something I overlooked after reading through the posts before mine. Although I myself do make the distinction between composition and soloing (Parker, Reinhart), thanks as well for bringing up the idea that some arranging and soloing can be thought of as composition. Staying within the paragdigm of "serious" music stipulated in the question (a term I understand but resent, and don't use myself), let me add to my little list: Ellington, Mingus, Monk, Coltrane.