It's any number of instruments that make a pleasing sound when played together.
Today, the modern orchestra is made of musical instruments divided into four sections -- strings, woodwinds, brass and percussion.
But by its true definition, early orchestras have been around for a thousand years, beginnig with the ancient Egyptians who are depicted playing together in unison on harps and flutes.
As new instruments were introduced to the musical landscape. orchestras grew in size. By the Middle Ages,musicians gathered together to play on lutes, bagpipes and fiddles. By the Rennaissance era, the makings of a modern orchestra truly began to take shape with the addition of violins, harpsichords, trumpets and trombones as a "consort" of musicians played together "in concert".
By the time of the Baroque period that followed, composer Johann Sebastian Bach was leading his orchestra while seated at the harpsichord. As fads came and went, the string section gained in popularity as the violin was joined by the viola, cello, and bass violin. The piano replaced the harpsichord.
By the classical period, both piano and string instuments were mainly responsible for the memorable, sweeping compositions we written by the likes of musical geniuses Mozart, Beethoven, Hayden, and others. By this time, composers also served as conductors who traditionally kept the beat by pounding a long pole on the floor. The pole later evolved into the baton.
As the Romantic music period century held sway in the 19th century, a no-holds-barred era of sound and fury added even more instruments to the classical orchestra including xylophones, drums, bells, and triangles.
at their best, combine a collection of instruments into one voice,
that speaks at the will of the conductor who interprets the imagination
of the composer in a way that audience can appreciate.
More about orchestras around the Web:
A finely tuned and cohesive presentation, at any level, is a
wonderful experience. Whether you're looking for information on
world class symphonies or background on classical musical instruments,
you'll find a world of information at these top sites ...
guide to the orchestra - A brief historical overview, typical
seating of a classical orchestra, photos & descriptions of
brass, string, percussion, keyboard and woodwind instruments,
the role of the conductor, related glossary of terms, audio files.