GDS II

GDS II is a data format used for design of integrated circuits (IC) by most designers. It is based on a stream of records which combined form file-headers, structures and elements.
A structure groups elements and indentifies this group by a name.
There are seven important elements: Boundarys, Boxes, Paths, Texts, Nodes, Structure References und Array References. The first three are geometrical elements used for the design. Texts label connections inside a structure. Nodes are used by graphical design-programs. The references link a structure defined somewhere in the GDS II-file to a specified position with optional transformations.