Cellos are part of the standard symphony orchestra, which usually includes eight to twelve cello players. The cello section, in standard orchestral seating, is located on stage left (the audience’s right) in the front, opposite the first violin section. However, some orchestras and conductors prefer switching the positioning of the viola and cello sections.
The principal cellist is the section leader, determining bowings for the section in conjunction with other string principals, playing solos and leading entrances (when the section begins to play its part). Principal players always sit closest to the audience.
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 low-register harmony for the orchestra. Often, the cello section plays the melody for a brief period, before returning to the harmony role. There are also cello concertos, which are orchestral pieces that feature a solo cellist accompanied by an entire orchestra.