What do the numbers mean when people write movie scripts?

Question by Kevin Kenny: What do the numbers mean when people write movie scripts?
I am not talking about the page number. There are numbers on the left of a lot of scrips that say like 1, 2, 3, 4, 1A, 1B, 2A, 2B, what does that mean???

Best answer:

Answer by Sound of Settling
What scene it is.

http://www.imdb.com/name/nm3314825/

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