Debussy wanted to distance himself from what he considered the emotional excess of the Romantics and instead wanted to write music that, through sound, created an ambience similar to that of the Impressionist painters and Symbolist poets of his day.
All books initially copyrighted in the US from 1964 through 1977 have had their copyrights automatically renewed (by law) and the copyrights are still in force. The initial copyright term was 28 years; the renewal was for 67 more years.
That's why, in many parts of the world, this day is also known as the World Book and Copyright Day. The first ever World Book Day was celebrated on April 23, 1995. The date as decided by UNESCO as it was also the death and birth anniversary of William Shakespeare, a world famous author. The date also coincided with the death anniversary of Miguel de Cervantes, who was a noted Spanish author.