It's going to be the first time I'll be trying to compose a piece to be played by an orchestra and I don't know much about orchestral strings numeration/disposition.
I just ran into this Composers initiative: http://patelconservatory.blogspot.com.es/2013/01/call-for-scores.html
and when reading the entry requirements, it's stated the following:
Scores should be written for the following instrumentation: 2 flutes, 1 oboe, 1 clarinet, 1 bassoon, 1 horn, strings (184.108.40.206.1).
What does the strings part actually mean?