Each master row in the Masters and Layers panel can have several types of sub-row underneath it, each representing a different kind of layer or related artifact.

•Master layer — the primary layer of a master, where most editing happens.

•Background layer — a parallel layer beside the master used for non-destructive subtraction and design reference. Appears under each master once content has been placed on it.

•Helper layers — auxiliary layers attached to a master for alternate sketches, work-in-progress shapes, or comparison overlays. A master can have any number of helper layers.

•Smart layers — for smart-component glyphs, the alternate layers along the glyph's smart axes. Smart layers are nested under their owning master and tagged with the smart-axis position they represent.

•Color members — for COLR color glyphs, the per-member layers that build up the colored composition.

•Reference artwork — imported bitmap or vector imagery used for tracing or visual reference. Replaces the older single-image background-image concept and supports multiple artworks per master.

 

For a smart-component glyph, the panel also shows a Smart Component group at the top containing the glyph's smart-axis definitions.