Cellos are part of the standard orchestra. Usually, the orchestra includes eight to twelve cellists. The cello section, in standard orchestral seating, is located on stage left (the audiences right) in the front, opposite to the first violin section. However, some orchestras prefer secondary orchestral seating, where the cello section is placed in the middle front, between the first violins and second violins.
The principal, or "first chair" cellist is the best cellist in the orchestra. In standard orchestra seating, he/she sits nearest to the conductor and the audience. In secondary orchestra seating, he/she sits nearest the conductor and stage left in comparison to the cellist next to him/her (the cellist sitting "second chair").
The cellos are a critical part of orchestral music; all symphonic works involve the cello section, and many pieces require cello soli or solos. Much of the time, cellos provide part of the harmony for the orchestra. On many occasions, the cello section will pick up the melody of the piece for a brief period of time, before returning to the harmony. There are also cello concertos, which are orchestral pieces in which a featured, solo cellist is accompanied by an entire orchestra.
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