Musical notation developed in the Middle Ages. The staff--lines to write notes upon--was developed around the first millennium, as were symbols for notes. These crucial inventions let music exist in its own right, outside of someone's mind. Innovations were driven by Roman Catholic church music, chants that were music, prayer, and rite all in one. Instruments of the time included the harp, distant ancestors of the violin, organs, the psalter, and various wind instruments.
Written music meant that it could be performed repeatedly. This spurred composers on. Musical experiments led to new musical genres by the 14th century. Harmony became important, and music was becoming a sophisticated affair. By the 16th century, composers were writing instrumental music for its own sake. Instrument instruction books were produced. Vocal music was rearranged for instruments, and the sonata appeared in Vienna.
The Baroque period occurred between 1600 and 1750. It was the age of Cervantes, Rembrandt, and Newton, and music both inspired and was inspired by the creative and intellectual environment. Monarchs, emperors, and popes were music fans and patrons; under their largesse, music flourished. Baroque composers--Vivaldi, Handel, Bach--intended to arouse emotions like rage, heroic passion, and religious ecstasy. Music's new psychological and emotional power elevated it among the art forms.
The Classic period followed the Baroque, lasting through the 18th century. The Enlightenment was taking place, that period promoting rights, equality, knowledge, and reason, spurring revolutions such as the American War of Independence in the process. People wanted music that spoke to everyone, free of restraint and independent of national boundaries. Instrumental music soared in prominence. Classic composers like Hayden and Mozart not only wrote music, but played music, too.
Though Beethoven studied music during the Classic period, he isn't easily typed. After absorbing the lessons of his age, he embarked on a singular musical journey marked by a depth of vision that made his music the model of the upcoming Romantic period. So original was Beethoven that, even late in life, his works mystified some contemporaries. Beethoven remarked that he was writing for a later age. His evocative music put self-expression front and center, changing the relationship of the world with music.
The Romantic period lasted most of the 19th century. Composers explored inner emotions, putting that ahead of musical convention. Instrumental music is perfect for this, able to describe feelings for which no words exist. Music became the highest calling of many artists, including non-musicians. The sympathy and overlap between art forms finds expression, for example, in the work of French poet Stéphane Mallarmé and compositions by composer Claude Debussy. Other Romantic composers include Schumann, Brahms, and Liszt.
The changing world of the late 19th and early 20th centuries made people crave their roots, including musical ones. Native Eastern Europe and Russian music, for instance, uses different scales and rhythms; some composers there cast off non-native conventions. In other places, music became abstract, alienating audiences. Elsewhere, music was used as propaganda, and some music was censored. In the 1970s, composers began returning to music that wider audiences might enjoy. Current composers feel free to draw from many sources: popular music, new technologies, world music, and styles of the past. Twentieth century composers include Bartók, Prokofiev, and Shostakovitch.