The orchestra has expanded over time. In the present day, a typical symphony orchestra consists of woodwinds, brass, percussion and strings. Other instruments such as the piano, harp and celeste may be occasionally added depending on the repertoire.

The first orchestras were made up of small groups of musicians who joined forces for civic and celebratory events. In the 11th century, the various families of instruments started to evolve, for instance the string family, which by this stage consisted of the ancestors of the modern violin, viola, cello and double bass. In Italy in the 16th century, noble families employed musicians for entertaining guests at the court. In the 17th century, opera was born, incorporating orchestral and vocal collaboration, which spread quickly throughout Europe. The orchestra became somewhat standardised in the classical period, under the influence of Joseph Haydn, who composed 106 symphonies and subsequently the innovative Ludwig van Beethoven.

Richard Wagner founded a large orchestra in Bayreuth in the 19th century to accompany his expansive musical dramas and his orchestral pieces were written with increasing complexity and scope. His influence was immense - for instance Das Rheingold calls for six harps. He brought about a revolution in orchestral composition and also elaborated on the role of the condutor in his writings. Conductors who studied his methods became increasingly influential themselves.

In the early twentieth century, orchestras were larger, better funded and more highly trained than ever before. As a result, composers were enabled to write bigger and more ambitious works. Gustav Mahler and Dmitri Shostakovich had at their disposal tremendous fuel for creativity and orchestras were capable of enormous forms of expression. What's more, the standard of performing reached ever-impressive levels with the availability of recordings.

In the present day, the use of the orchestra has remains the pinnacle of expression in classical music, although it is possible for composers to add any array of unconventional instruments to the mix.

...the use of the orchestra has remains the pinnacle of expression in classical music...