Schubert wrote four Impromptus…
But this is by far the most famous and continues to be one of the most famous pieces ever written. I chose this recording, not only because it is excellent, but you can see the player. I’d like to get rid of the stupid chandelier above, but nothing is perfect.
Here is a biography. Read it if you have time.
But first remember this, most of all; he died at the age of 31. And much of his greatest music was never heard until after his death. He was so poor, he was only finally able to buy his own piano during the last year of his life.
We can only imagine what he would have written if he had lived to age 70.