There have always been groups of musicians playing together.
The word "orchestra" is Greek in origins, and originally meant the place where Greek chorus sang and danced.
In the Baroque orchestra (1600-1760), the strings and winds played the same sort of music melodically and rhythmically and there were from 10 to 30 players.
After the Baroque, developed was the Classical orchestra (1750-1830). It used 30 to 60 players and had developed into a flexible and colourful instrument to which composers could entrust their most powerful and dramatic musical conceptions.
Romantic orchestras (1815-1910) had as many as 100 players or more, and featured greater use of brass and piano.
The modern present symphony orchestra varies in size, but typically has a strength of about 100 and comprises some 16 first and second violins, 14 violas, 14 cellos and 8 - 10 double basses.
