GDSII stream format (GDSII), is a binary database file format which is the de facto industry standard for electronic design automation (EDA) data exchange of integrated circuit (IC) or IC layout artwork.
Objects contained in a GDSII file are grouped by assigning numeric attributes to them including a "layer number", "datatype" or "texttype".
As of April 2008, many EDA software vendors have moved to the stream format OASIS, which replaced GDSII.
[2] As the GDSII stream format is a de facto standard, it is supported by nearly all EDA software.
GDS II Graphic Design System User's Operating Manual, First Edition 1978.