Classical music, strictly defined, means music produced in the Western world between 1750 and 1820. This music included opera, chamber music, choral pieces, and music requiring a full orchestra. To most, however, the term refers to all of the above types of music within most time periods before the 20th century.
In its limited definition, classical music includes the works of Haydn, Mozart and Beethoven. From Mozart alone, there are a huge range of pieces to enjoy, as he wrote symphonies, music for quartets and quintets, chamber orchestra pieces, choral pieces, piano concertos, and entire operas. In total, he wrote over 600 musical pieces. Mozart is perhaps best known for his opera, The Magic Flute, although most people also recognize Eine Kleine Nachtmusik, as well as a number of his symphonies and concertos.
Classical music would not be quite the same without Beethoven, who is particularly known for his symphonies. Beethoven’s sixth symphony is probably most recognized because of its pastorale, a section of music used in the Disney film Fantasia. The achingly beautiful Moonlight Sonata was also written by him. Beethoven wrote only one opera, Fidelio, and his genius rests in his symphonies and piano concertos.
Haydn has often been referred to as the “father of classical music,” as his work during this era forms the basis of influence for many others. Ironically, though he is considered the progenitor of the classical era, he is less familiar to most audiences than the composers mentioned above. His Symphony no. 94, The Surprise Symphony, is among his best known works.
Classical music in the broader definition evokes such composers as Bach, who preceded the more rigidly defined era and is more rightly classed in the Baroque period. Vivaldi, perhaps best remembered for The Four Seasons is also of the Baroque period. Handel’s Messiah is well known to the many who participate in sing-alongs during the Christmas season.
The Romantic Period, which follows directly after the classical period, is known for its emotive qualities. Mahler and Sibelius stand out and tend to be familiar to most. Wagner is perhaps the most frequently recognized of the Romantic composers, his work stormy and grand, and his many operas still performed regularly today.
"Classical" music may also refer to the native and folk music of any country, although the styles vary greatly, depending upon available instruments. For example, the classical music of Indonesia, with its use of the gamelan, is vastly different from what most would consider classical in the western world. Folk traditions in other countries were often quite influential to western music, however, as musicians of the baroque and classical periods often adapted their works from folk music.