Outline is the term we use to describe a gathering of Segments as a structural annotation. An Outline is the group containing one or more Segments. By grouping Segments into Outlines you will be able to more easily manage you content for Collation and drafting for example to collatet all chapter one Segments from your witness Materials you would put them together in a single Outline. By collecting Segments into an Outline you will be creating a well-structured set of Segments to facilitate collation under the draft tab.
You cannot collate any material untill you have put the desired material in a segment and gathered the desired segments together to make an Outline.