Schubert was an extremely musical person and one of the greatest composers of all time. Unlike J.S. Bach, who was trained in the family profession from an early age, and Mozart, who was raised like a hothouse plant and pushed as a child prodigy by his father, Schubert came from a family of schoolteachers who were only amateur musicians. But it became obvious early on that he was especially gifted. He started composing at age 13 while at the Stadtkonvikt school in Vienna, and he received tutelage in composition from Mozart's former rival, Antonio Salieri, who stated that Schubert was a genius and another Mozart. But the myopic Schubert did not have an easy time of it; he contracted syphilis, suffered from it for several years, and died prematurely at age 31. He became well-known as a writer of songs in his lifetime, but his orchestral, chamber music, and operatic works didn't get published until years or even decades after his death. Some of his compositions have only recently been published.
This little paperback by Maurice J.E. Brown, with a comprehensive list of compositions added by Eric Sams, provides a good introduction to Schubert and his music for those who have only a passing knowledge of the subject. The book is divided into three parts: the first briefly relates Schubert's life and musical development; the second discusses Schubert's music by genre -- songs, song cycles, instrumental compositions, music for the theatre, and church and other choral music; and the third is a listing of all of Schubert's known compositions organized by categories and by Deutsch number within categories. Schubert wrote over 600 songs and about 200 other compositions, so the listing is quite long. Looking at the list, one becomes aware that Schubert left many of his compositions unfinished. Whether or not he intended to get back to some of them, had he lived, is of course unknown, but some are treasures even in truncated form, such as the Quartettsatz and of course the Unfinished Symphony.
The book also has a lengthy bibliography, eleven black-and-white illustrations, and uses Wilhelm Reider's well-known 1825 watercolor portrait of Schubert for the cover.
One shortcoming of the book is that the discussions of Schubert's music are quite brief and tend to overlook his early compositions, especially the orchestral ones, even though many of these are quite splendid and certainly worth hearing and discussing. The author also has rather strong opinions about some of Schubert's works; these opinions don't always agree with what I would say.
For a more comprehensive and in-depth look at Schubert's life and music, I suggest reading "Schubert: the Music and the Man," by Brian Newbould. Newbould is probably the person who is most knowledgeable about Schubert and his prodigious output.
On the Schubert monument erected in 1830 in Vienna is the following inscribed epitaph (translated): "The art of music here entombed a rich possession, but even fairer hopes." One wonders what other great masterpieces Schubert would have written had he lived to a ripe old age.