SORT ORDER?

If you're referring to the new feature, it basically just determines which stories will show up first when people look at your profile. For example, if you set the sort order number to "1" in a story's settings, that will be the first story people see when they check your profile, if you set it to "2" it'll be second, and so on. It's completely optional, and if you leave it blank, your stories will be ordered by the time they were created as they normally are.