His early experiences greatly increased Gershwin's knowledge of jazz and popular music. He enjoyed especially the songs of Irving Berlin and Jerome Kern—referring to Berlin as “America's Franz Schubert” and stating that Kern was “the first composer who made me conscious that most popular music was of inferior quality, and that musical comedy was made of better material”—and he was inspired by their work to compose for the Broadway stage. In 1919 entertainer Al Jolson performed the Gershwin song Swanee in the musical Sinbad; it became an enormous success, selling more than two million recordings and a million copies of sheet music, and making Gershwin an overnight celebrity. Also in 1919, Gershwin composed his first “serious” work, the Lullaby for string quartet. A study in harmony that Gershwin composed as an exercise for Kilenyi, Lullaby's delicate beauty transcends its academic origins.

During the next few years, Gershwin contributed songs to various Broadway shows and revues. From 1920 to 1924 he composed scores for the annual productions of George White's Scandals, the popular variety revue, producing such standards as (I'll Build a) Stairway to Paradise and Somebody Loves Me. For the Scandals production of 1922, Gershwin convinced producer White to incorporate a one-act jazz opera. Legend has it that Gershwin composed Rhapsody in Blue, perhaps his best-known work, in three weeks' time. Owing to the haste in which it was written, Rhapsody in Blue was somewhat unfinished at its premiere. Gershwin improvised much of the piano solo during the performance, and conductor Whiteman had to rely on a nod from Gershwin to cue the orchestra at the end of the solo. Nevertheless, the piece was a resounding success and brought Gershwin worldwide fame. The revolutionary work incorporated trademarks of the jazz idiom (blue notes, syncopated rhythms, onomatopoeic instrumental effects) into a symphonic context.

Leonard Bernstein plays G. Gershwin – Rhapsody in Blue

For the remainder of his career, Gershwin devoted himself to both popular songs and orchestral compositions. His Broadway shows from the 1920s and '30s featured numerous songs that became standards: Fascinating Rhythm, Oh, Lady Be Good, Sweet and Low-Down, Do, Do, Do, Someone to Watch over Me, Strike Up the Band, The Man I Love, 'S Wonderful, I've Got a Crush on You, Bidin' My Time, Embraceable You, But Not for Me, Of Thee I Sing, and Isn't It a Pity. He also composed several songs for Hollywood films, such as Let's Call the Whole Thing Off, They All Laughed, They Can't Take That Away from Me, A Foggy Day, Nice Work if You Can Get It, Love Walked In, and Love Is Here to Stay. His lyricist for nearly all of these tunes was his older brother, Ira, whose glib, witty lyrics—often punctuated with slang, puns, and wordplay—received nearly as much acclaim as George's compositions. The Gershwin brothers comprised a somewhat unique songwriting partnership in that George's melodies usually came first—a reverse of the process employed by most composing teams.

Gershwin's piano score for I Got Rhythm was part of a larger project begun in 1931, George Gershwin's Songbook. A collection of Gershwin's personal favorites among his many hit tunes, it featured the composer's own adaptations designed “for the above-average pianist.”

An American in Paris (1928), Gershwin's second-most famous orchestral composition, was inspired by the composer's trips to Paris throughout the 1920s. His stated intention with the work was to “portray the impressions of an American visitor in Paris as he strolls about the city, listens to various street noises, and absorbs the French atmosphere”; for this purpose, Gershwin incorporated such touches of verisimilitude as real French taxi horns. It is this piece that perhaps best represents Gershwin's employment of both jazz and classical forms.

G.Gershwin – An American in Paris

An American in Paris seemed more like a ballet than symphony and, indeed, the piece gained its most lasting fame 23 years after its premiere, when it was used by Gene Kelly for the closing ballet sequence of the classic, eponymous film musical in 1951.

George Gershwin’s most enduring and respected Broadway work, Porgy and Bess, was lukewarmly received upon its premiere in 1935. Gershwin's American Folk Opera was inspired by the DuBose Heyward novel Porgy (1925) and featured a libretto and lyrics by Ira and the husband-wife team of DuBose and Dorothy Heyward. In preparation for the show, Gershwin spent time in the rural South, studying firsthand the music and lifestyle of impoverished African Americans. Theatre critics received the premiere production enthusiastically, but highbrow music critics were derisive, distressed that “lowly” popular music should be incorporated into an opera structure. Black audiences throughout the years have criticized the work for its condescending depiction of stereotyped characters and for Gershwin's inauthentic appropriation of black musical forms. Nevertheless, Gershwin's music—including such standards as Summertime, It Ain't Necessarily So, Bess, You Is My Woman Now, and I Got Plenty O' Nuttin' —transcended early criticism to attain a revered niche in the musical world, largely because it successfully amalgamates various musical cultures to evoke something uniquely American and wholly Gershwin. Many now consider the score from Porgy and Bess to be Gershwin's greatest masterpiece.

Gershwin's music remains a subject of debate among prominent international conductors, composers, and music scholars, some of whom find his works for orchestra to be naively structured, little more than catchy melodies strung together by the barest of musical links. In 1954, Leonard Bernstein summed up the feelings of many classical musicians, saying, “The themes are terrific—inspired, God-given. I don't think there has been such an inspired melodist on this earth since Tchaikovsky. But if you want to speak of a composer, that's another matter.”

Gershwin died July 11, 1937 in Hollywood, California at the young age of 39 years old. Some critics may say there are indeed weak spots, but who cares about them when there is greatness to live on through his music.

Dame Kiri Te Kanawa sings "Summertime" - "Porgy and Bess"