The term 'classical music' did not appear until the early 19th century, its earliest reference recorded by the Oxford English Dictionary is from about 1836. There are various styles of music that fall into the definition of classical; these include symphonies, opera, sonatas and chamber music.

Common with its musical characteristics are the use of dynamics and orchestral colour in a thematic way; the use of rhythm, including periodic structure and harmonic rhythm, to provide structure in large-scale forms, along with techniques of modulation to build longer spans of tension and release.

This form of music is easily identifiable by its wide use of instruments of varying tones and pitches used to create a fullness of sound. Classical music was hugely affected by the invention and modification of instruments throughout time. Different combinations of instruments can be used for classical music, composers wrote for different groupings including orchestras, wind ensembles or various combinations of instruments for chamber music. Instruments like the piano, violins, violas, flutes and trumpets were used. The human voice was also used, which created its own series of classical music, the Opera. Composers also wrote solo pieces for a specific instrument, accompanied by piano.

Classical music composers often aspired to instil in their music a very complex relationship between its affective (emotional) content and the intellectual means by which is it achieved. Frequently works make use of musical development, the process by which a musical idea is repeated in different contexts or in altered form. Music scholars study this use of form and repetition and seek to unlock the reasons why some composers manage to execute the technique effectively while others simply fall into the trap of further harming their compositions. The reason we remember some classical tunes so well is down to this clever technique.

Another identifier of the classical style is the way it is passed on accurately using written music notation rather by oral transmission, which would undoubtedly create numerous variations. This is a very good method of preserving the piece as the written music contains the technical instructions for performing the work. Music notation from the classical era does however leave some interpretation open in several areas like performance, apart from directions for dynamics, tempo and expression; this is left to the discretion of the performers, who are guided by their personal experience and musical education or the direction of a music director or conductor.

Essential Reference: A list of the most famous classical music composers:

Ludwig Van Beethoven - 1770-1827
Wolfgang Amadeus Mozart - 1756-1791
Johann Sebastian Bach - 1685-1750
Claude Debussy - 1862-1918
Franz Liszt - 1811-1886Frederic Chopin - 1810-1849
Felix Mendelssohn - 1809-1847
Antonin Dvorak - 1841-1904
Giuseppe Verdi - 1813-1901
Gustav Mahler - 1860-1911
Hector Berlioz - 1803-1869
Richard Wagner - 1813-1883
Joseph Haydn - 1732-1809
Johannes Brahms - 1833-1897
Franz Schubert - 1797-1828
Peter Ilyich Tchaikovsky - 1840-1893

Alan Hovahaness 1911-2000
Ralph Vaughan Williams 1872-1958
Anton Bruckner - 1824-1896

To appreciate the various styles of this genre of music, many of these composer's works should be explored to understand the richness and variety of the form.