Most drafts that I have seen on MTGO use a set of numbers after the format. I think it describes what matches are played after the drafting portion. For example:
Modern Masters 2015 6-2-2-2
Modern Masters 2015 refers to the types of boosters that will be opened. What does the "6-2-2-2" mean?
I have also seen "8-4" as a common postfix. Are there others, and if so what do they mean?